2 cents mode -
That boat is meant to be a "speed" boat. If you don't get 100-150hp on the boat it will be unsellable in the future. Or it will have to be a giveaway.
99% of people looking for a speed boat will expect it to go fast.
I don't think that transom is setup or strong enough to hang an outboard of that weight and size.
- Option 1 - 4 banger gas and v-drive
- Option 2 - Rebuild/strengthen the transom and 100-150hp outboard
- Option 3 - Some diesel solution that pushes the boat like a trawler
The easiest is option 2. The most desirable is Option 1.
oh... Option 4. Sink it it and buy a sailboat