Based on what you've said above, here's my next novel. Let's go front to back and leave the engine/trans to last.
You first want to look at a v8 cutlass or regal for the radiator top plate. It holds the larger core to the top of your existing g radiator, and bolts on where your plastic shroud attaches now. A turbo v6 regal from 1986-87 with the intercooler also has one, but these often cost more as the turbo guys need them for the specific extra studs that hold the ac lInes in those cars.
You now have a choice: grab the V8 fan shroud off that same regal/cutlass if you are using a clutch driven fan off the water pump, OR, do not buy that shroud and instead remove the rotating mass and drag of that fan by using an electric fan setup.
Next, you need the frame side of the sbc motor mounts. These can come from any v8 monte carlo, a v8 grand prix, or, certain Canadian built and Canadian sold v8 cutlass cars. Being in new england, I saw a few of them around in my time living there, especially far northern areas, as the Canadian cars had a sbc rather than the 307 from the factory.
Springs/shocks are your choice, same with potential poly bushings or rubber in the suspension while you have it apart.
It sounds like you are going carbed, which is what I will base all the rest off of, otherwise you want a 4.3 monte or turbo 3.8 regal gas tank for the internal baffle provisions, and would need to upgrade fuel lines/in tank fuel pump and sending unit as well.
Brings us to driveline itself, the meat of what you are after. This time I go back to front, just to make you squirm a bit in anticipation.
For stock power levels your 7.5" rear end will live, if you don't abuse it and do burnouts, flogging on the car. The highway gears dont go a ton to help you either. To the extent you want a short term change for new steeper gearing per that calculator I showed you before, you have the following options: cheapest upgrade to gear, without adding strength, is a 3.73 rear from a monte ss. For a few hundred more than that, I have a friend in western mass who still parts out gbodies all the time, and always gets 8.5" rear ends from 442 (3.73) and ttype/gn regals (3.42). To go with the 8.5 you need the matching driveshaft as well.
Transmission is your next stop and that th200c you've got isn't worth bothering with. It won't hold up well at all, doesn't have the correct bolt pattern to mate to a sbc, and to be honest, rather than waste money on an adapter you are better off buying what you want to use longer term anyways. For ease of sourcing I say 200-4r, likely looking to a Montecarlo donor here, although come cars did have dual bolt pattern bellhousings. With the 2004r you grab the matching factory crossmember on the cheap, or even modify the one you have, and you already have the factory holes in place on your frame rails to bolt it in place, no drilling. Remember to swap the speedo driven gear to match whatever rear end you are choosing to use. (I like plug and play) getting good used or recently rebuilt from a wrecked car or abandoned project is easy, and gets you driving for now while you save for a full rebuild later. No need to spend extra on a fully rebuilt unit now.
Ahh, and your favorite, the engine. From what you describe, and in the interests of cheap, I would like to recommend a 1986 350 from a full size chevy/gmc truck. That truck 350 will have a 4 bolt main, and, 1986 was when they phased in the one piece rear main seal instead of the 2 piece design. This means no removing the rear main cap to change it out, you can do it while the Trans is out. Also, 1986 was the final year of the older style cylinder heads before going to the center bolt design. Tons and tons of CHEAP go fast parts and carbed intakes for the 86-down blocks, the center bolt heads usually leave you paying higher prices or going new. The 1986 was the hybrid block - had the newer oil pan, flywheel counterbalance, and lower block casting design with 1pc rear main of the 87-up motors that were so reliable out to 300k, 400k miles, but, it was drilled on the top end for the heads and old school parts of 1985 down which makes it cheaper to build.
A grand prix/monte/canadian cutlass can give you what you need for the ac condenser for the lines to match up right and keep your air, but, beware using headers from a different application. Even if they can be made to fit the frame rails and such, they can sometimes interfere with mounting your front accessories.
Let me know if that instills any questions...and if I think of more, I'll add it.
You first want to look at a v8 cutlass or regal for the radiator top plate. It holds the larger core to the top of your existing g radiator, and bolts on where your plastic shroud attaches now. A turbo v6 regal from 1986-87 with the intercooler also has one, but these often cost more as the turbo guys need them for the specific extra studs that hold the ac lInes in those cars.
You now have a choice: grab the V8 fan shroud off that same regal/cutlass if you are using a clutch driven fan off the water pump, OR, do not buy that shroud and instead remove the rotating mass and drag of that fan by using an electric fan setup.
Next, you need the frame side of the sbc motor mounts. These can come from any v8 monte carlo, a v8 grand prix, or, certain Canadian built and Canadian sold v8 cutlass cars. Being in new england, I saw a few of them around in my time living there, especially far northern areas, as the Canadian cars had a sbc rather than the 307 from the factory.
Springs/shocks are your choice, same with potential poly bushings or rubber in the suspension while you have it apart.
It sounds like you are going carbed, which is what I will base all the rest off of, otherwise you want a 4.3 monte or turbo 3.8 regal gas tank for the internal baffle provisions, and would need to upgrade fuel lines/in tank fuel pump and sending unit as well.
Brings us to driveline itself, the meat of what you are after. This time I go back to front, just to make you squirm a bit in anticipation.
For stock power levels your 7.5" rear end will live, if you don't abuse it and do burnouts, flogging on the car. The highway gears dont go a ton to help you either. To the extent you want a short term change for new steeper gearing per that calculator I showed you before, you have the following options: cheapest upgrade to gear, without adding strength, is a 3.73 rear from a monte ss. For a few hundred more than that, I have a friend in western mass who still parts out gbodies all the time, and always gets 8.5" rear ends from 442 (3.73) and ttype/gn regals (3.42). To go with the 8.5 you need the matching driveshaft as well.
Transmission is your next stop and that th200c you've got isn't worth bothering with. It won't hold up well at all, doesn't have the correct bolt pattern to mate to a sbc, and to be honest, rather than waste money on an adapter you are better off buying what you want to use longer term anyways. For ease of sourcing I say 200-4r, likely looking to a Montecarlo donor here, although come cars did have dual bolt pattern bellhousings. With the 2004r you grab the matching factory crossmember on the cheap, or even modify the one you have, and you already have the factory holes in place on your frame rails to bolt it in place, no drilling. Remember to swap the speedo driven gear to match whatever rear end you are choosing to use. (I like plug and play) getting good used or recently rebuilt from a wrecked car or abandoned project is easy, and gets you driving for now while you save for a full rebuild later. No need to spend extra on a fully rebuilt unit now.
Ahh, and your favorite, the engine. From what you describe, and in the interests of cheap, I would like to recommend a 1986 350 from a full size chevy/gmc truck. That truck 350 will have a 4 bolt main, and, 1986 was when they phased in the one piece rear main seal instead of the 2 piece design. This means no removing the rear main cap to change it out, you can do it while the Trans is out. Also, 1986 was the final year of the older style cylinder heads before going to the center bolt design. Tons and tons of CHEAP go fast parts and carbed intakes for the 86-down blocks, the center bolt heads usually leave you paying higher prices or going new. The 1986 was the hybrid block - had the newer oil pan, flywheel counterbalance, and lower block casting design with 1pc rear main of the 87-up motors that were so reliable out to 300k, 400k miles, but, it was drilled on the top end for the heads and old school parts of 1985 down which makes it cheaper to build.
A grand prix/monte/canadian cutlass can give you what you need for the ac condenser for the lines to match up right and keep your air, but, beware using headers from a different application. Even if they can be made to fit the frame rails and such, they can sometimes interfere with mounting your front accessories.
Let me know if that instills any questions...and if I think of more, I'll add it.
