Reading all this, I have to ask- will a later powerhead fit on an earlier tower? Pardon my ignorance, but have not had a ten horse look at me crosseyed and dared me to buy it- yet.
If you have too many, AND not enough, you're a collector.
I believe the thermostat cooled powerheads are interchangeable, but not with the non-thermo powerheads. The 1958 and prior cylinder heads have the wings for the cowling supports. And, due to the thermos, you can’t put a ’58 cylinder head on a ’59 & up block.
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