My 65 C10 came with a 6 cylinder but I want to install a small block V8. What do I need to add to my chassis in order to bolt in the larger engine?
The original perches for a 230ci are correct and in the correct location for a small block V8. Watch out, if the valve covers are really tall they will bump into the firewall. Some folks move the engine forward an few inches.
If you have the perches for a 292ci, then one is correct (same as a 230ci perch) and the other one is NOT correct.
I am also planning to change from my current 3 speed manual to a more modern automatic trans. Do I need different engine mounts on the frame and/or different crossmember for holding up the new trans, etc.?
Installing a modern AT will require removal of the current transmission crossmember. You'll need to buy or make a new crossmember for the AT. You will need to cut the drive shaft to the correct length.
All of the above is from memory from when I researched the issue for my 1965 C10. So it's not info from personal experience, but I think it's accurate. I chose to keep my inline 6 and I installed a floor shift 5 speed MT with OD.
