Large Model Boats I Have A 1999 Glastron 175 Sx With 3.0 Volvo Penta, How Large Of Motor Will Fit?

I have a 1999 glastron 175 sx with 3.0 volvo penta, how large of motor will fit? - large model boats

I have a 1999 Glastron boat, the SX-175 and has a 4-cylinder and 3.0 Volvo Penta, and I have a bigger engine in it, but the entire unit, which exists outside use. What should I engine. Or you could buy a new head or used for th engine had a different idea, I'm in WI