JC, a 'crate engine' off the Web will very likely be a 351-W, not the original Cleveland, since rebuildable 351-Cs are in very short supply these days. Swapping in a Windsor might open up a fresh can of trouble with things not bolting up right. I vote for reworking what you have whether you do it or someone else. As Doug said, ALL these engines have their specific quirks and knowledge doesn't translate one to another.
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