I have a 2GM20F in my '79 H30C.
It seems to be lighter than the original YSM12 that came with the boat originally. So, I don't think weight would be a problem if your hull and stringers are as stoutly built as mine.
There is room, I think, if you can adjust the motor mount locations on the stringers. But you may have to shorten the prop shaft.
So, lots of measuring to do with a qualified engine intaller before you
pull the trigger.
If you'd like I can give you the mech'e number who did my install. And since he's located in Daytona, but goes far and wide for customers, he might be willing to come to you.
If you don't have a suitable yard there, Daytona Boat Works is a reputable yard here.
Send me a PM if you have questions.
G.