ive heard that almost all chevy engine mounts are the same and was wondering if i could swap a 256 with a v8 without new engine/frame mounts because ive swapped a buick 350 with a 455 and everyone told me the 455 would fit right in but i ended up having to buy new engine mount frame mounts and oilpan..

 

not sure about it 100% but it should fit right in, i seen someone do a v6-v8 swap on a 3rd gen with no probs. you might just have to move the mounts ahead a bit but there are holes to do it without probs.

 

Back in high school (about 100 yrs ago) I helped a friend of mine swap a V-6 for a V-8 in a mid 70's camaro, and if memory serves, all we had to do was move the motor mounts to the forward holes in the frame.