Powerhead compatibility

[doug9238]

I have a 1978 Johnson Magna V4 Sea-horse (model # 85ML78C) that has a blown powerhead due to running with straight gas. There is a complete 1977 Johnson 85HP (not sure of model #) for sale locally that is missing the lower unit.

Does anyone know if I could purchase this and make one good motor out of two?

Thanks,
Doug