I'm swapping out my Mercruiser 4.3 V6 for a 5.7 V8 (350), I'm thinking it should be a straightforward swap. I have an Alpha 1 Gen 2 outdrive, and I know that I need to modify the upper gear from 1:81 to 1:47, and the only other item is the exhaust elbows are different and I have them already...