Yamaha 70, Prop to Jet Conversion - Transom Height?

[AlaskaRiverRat]

Presently I have a early 90's (92?) 70 hp 2-cycle Yamaha with prop that I am pushing a flat bottomed aluminum setnet skiff with. I'd like to switch the lower unit from prop to a jet unit.<br /><br />My question is - can I switch from prop to jet lower unit and not have to change the transom height? I've got a 20 inch transom. Does Yamaha design their outboards so if the transom height is correct for a prop configuration, it will also be correct when you switch to a jet unit?<br /><br />Anyone know the answer on this? Thanks.