1988 V20 steplift/305 chevy, mercruiser drive.

[UBHSTRY]

I am working on one of these, I have been looking for some information on how much power the drive can handle on these boats. Also, what could be done to them if say, you wanted to stuff some decent power in it. IE: Chevy 383, nice aluminum heads, good intake, roller rockers and cam, and a holley 600. Mild on the cam. But capable of spinning to 65-6800rpm.