351m in '65 pony

[thunderbolt]

I think you are in for some work here. There have been people who put 351C's in early cars and the 351W conversion is well liked. But the 351m is a slightly wider than the the 351C which means exhaust manifold fit will be a real bear. Second problem, what is the condition of this 351m. This engine would be my last canidate for a rebuild as it has all the problems of the 400 and none of the benefits of the 351C. I would keep hunting for a 302 if it was me.