trying to swap a b-body rear into the monte

well it has been done before but the description was pretty imprecise, and no mention was made of binding, or aftermarket control arms, so what the hell i'll try it. i just won a 95 caprice 9c1 rear off ebay and will be picking it up on saturday.
what i plan on doing is getting the measurements first (since there's already a rear in the car, and i want to keep her driving as much as possible) and figure out the geometry. if things look close enough i'll try a loose bolt in.
any and all advice is requested.
i do know that the axle is wider, that just eliminates the wheel spacers i was going to use. and i know that the lug pattern is 5x5. worst case i get new axles with a 5x4.75 pattern. other than that i'll be making it up as i go.
i'll update this as it happens.

heh I scrapped one of these rearends recently

Click to expand...

DAMN YOU!!!! damn you to hell!!!!
just kidding :lol:
supposedly the axle is 63in flange to flange, a gbody is something like 58. i was looking at running a 3in spacer, each side, so cutting 2.5in out of the spacer sounds good to me.
re. the control arm points, the swap has been done (search maliburacing.com) and hell, people do the a-body swap and they don't line up.
so i figured it's worth a shot. if it don't work, sh*t happens. if it does work... 😀

yeah, the way the guy said it on maliburacing was that he just had to elongate the holes rearward. since i have tubular arms the bolt holes are through 1/4in plate so i should be good.
we'll find out. i plan on getting constant pics and detailing what i do so it can be easily repeated.

i'm too tired to put the pics up but heres what i've got. (it's not much yet) the rear geometry is the same, 45* for the UCA's and 75* (from the axle) for the LCA's.
the g-body LCA's are 44.75in apart, the b-body's are 46in so it's only .625in difference per side. even poly bushings should be good but i'd highly recommend a heim or johnny joint for proper movement. although the stock rubber on the axle side would be fine, it's just not the best for handling.
the G LCA's sit 1.5in to the rear of the axle center, i forgot to check the b-body but i think they sit a little farther to the rear, not by much(maybe 1/2in?).
i have to get some more measurements for the UCA axle mounts too. the G's sit 7.75in apart and the B's are 12in, but the G's are centered on the axle tube while the B's sit forward. i just have to do the trig and figure out the center point.
for the shock mount you could relocate the hose hold down bolt (with disc brakes) and widen the hole for the shock bolt, or relocate the hose and use the oval hole below it. obviously if you use the oval hole it should be filled in. the original shock mount sits on the front of the axle, so i would just cut that off.
i forgot to look but IIRC the G's brake hose from the frame is on the D/S axle. that would need to be moved to the center of the axle, or a new braket made on the B's axle tube.
wheel mountind points are 61.5in apart with the rotors on. the outer rotor surface is 58.5in apart.
i doubt my measurements are EXACT, but they should be within 1/4in total. if you're under your car, i would appreciate if you could confirm them for me.
as always all comments or advice is welcome.

and the rear is from a park rangers car so it shouldn't have been TOO badly beaten 🙂

the spring perches are in the same spot, the UCA's are on the same line/center point.
from what i'm getting, you will need to shorten the UCA by 3in.
the LCA axle mounting points are in the same spot.
so from what i'm seeing you have to shorten the UCA, get good bushings or cut/weld the LCA's for a .6in spread, get a longer body-axle brake hose, and modify the holes for the shocks.
is there anything i missed/screwed up?