Hi and welcome to the forums...Congrats on the new boat.
Measure from the top of the transom where the engine sits to the bottom keel of the boat. That distance is what your engine is. (I think, and I may be wrong) that all V20's are set for 20" engines, unless there is a jackplate on the transom or unless the transom has been raised.
You're correct, a 150 is the engine of choice for these boats, BUT 200's and 225's are not unheard of. In fact, there are several members here that run them on their boats, including this writer. Get what you can afford. and remember...
We love to see projects...it gives us all ideas, and at the same time we can give advice easier.
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1987 V20 w/1987 150HP Yamaha on a Shoreland'r Trailer
1978 16.5 Airslot w/1996 120HP Force on a Four Winns trailer
1996 V21 w/1993 200HP Mercury on a Shoreline Trailer
All towed by a 5.7L Hemi Durango.
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