Yes, that's it. I'm not looking for power where I need to use high octane gas and waste a lot of it. 265 HP should be plenty. There is a motor with vortex heads that is capable of running a mechanical fuel pump, but I'd have to change the cam (If I understand that correctly) or find a different solution. I'm guessing there is an electrical fuel pump of some kind.
From what I remember, the differences from an older sbc vs. a Vortec era:
Oil pans are different (1pc crank seal vs 2pc.).
Flywheels are different (1pc vs 2pc bolt pattern).
Balancer needs to match timing set.
Intake.
Valve covers.
Fuel pump (early blocks have the FP boss, later don't; cam has to have FP lobe).
Exhaust should most change over (apparently there are some weird configurations that have an extra bolt hole requirement).
Not 100% sure on the distributor interchange.