Re: 302 to 429/ 460 Swap
If you have a c4 transmission,you have an automatic transmission, not a manual. Do you has a clutch pedal?
On a '72 it is not likely you have a manual transmission with a 302 unless it was done after market.
as for a 429/460 engine swap from a 302 you will need a complete 429/460 engine including all the accessories such as ps,pulies, fan, shroud,and Radiator. 429/460 motor mounts, Front springs designed for 429/460, possibly larger front brakes, A big block transmission, relocating the transmission crossmmber for a bigblock transmission, and posable drive shaft change.
C4 and FMX automatic transmissions have interchangeable bell housings for small blocks abd big blocks while if is a c6 transmission is all one piece body that does not have interchangeable bell housing and you would ned to swap out the entire transmission,
There are lots of threads on this subject on this site as well as others.
An easy engine swap would be to a 351C or 351W very few additional parts for this swap. a 351M/400 would require most the same changes as a 429/460 swap would require.