You will need to change both the Engine and Frame front Motor Mounts. If my memory serves me correctly the rear mount is the same - Consider changing the Radiator to a V8 Radiator and the V8 Front Coils springs are heavier. This swap is an easy one.
'72 V-8 Novas with air conditioning came with a 3-core radiator and an air deflector that mounted underneath it, which forced air coming from the grille through the radiator rather than out between the radiator and bumper. The deflector is not available any more from GM, but you could make one pretty easily, and it does seem to help.
Use your current flywheel/flexplate on the 350, the bolt pattern is the same.
If you're using a manual trans, upgrade to a 10.4" clutch. It'll bolt to the same flywheel, you just need a pressure plate, disc, & throwout bearing. I'd advise using a V-8 clutch adjuster rod, it's stronger than the 6-cylinder unit.