1988 V20 steplift/305 chevy, mercruiser drive.

[spareparts]

The drives don't like more than about 5500 rpm, you can upgrade the lower end by replacing the shift pin with an outboard style(hi performance) screw in shift pin(you'll have to dissasemble the lower). Thats the first thing to go boom. I'd run a twin drive shower to keep the upper cool, and add an external resivoir for the gear lube, bigger the resevoir, the better. I'd also recomend running merc high performance gear lube(its made by bellray), its good stuff, its like climbing lube