After seeing no response to your question, I thought I would let you know that the intake manifolds that fit the 215 blocks are all the same. This is NOT your overheating problem. I would check out the radiator next. They have a tendency to plug up and need to be cleaned, channel by channel, with a flat rod, both tanks removed. A boil-out cleaning job will NOT do the trick! A re-core will do the trick too, just more $’s!
I have built a “Jetfire wagon” fun! You can build one too. Have fun………..