Allot more to building a successful jet than hanging a pump on any of various assorted hulls.
Going to have to agree with Steve... as short and to the point as he is, his opinion is spot on. An overpowered pump with a relatively small intake area on a hull not moving fast enough to, or designed to feed the pump a clean water stream is going to be an eternal PITB that will end in cavitation damaged impellers, and a generally disappointing result.
*A jet pump MUST have a hull that keeps the foot in the water.
*A jet MUST have a design that keeps a positive pressure on the "suction" piece at all times, including cornering, flat out running.
*The intake must be deep enough to not have problems with parasitic cavitation under sudden acceleration.
*The hull has to provide a clean, uninterrupted flow column to the intake, and be able to do so through the entire expected speed range.
In the case of an overly flat hull around the intake, the surface boundary layer creates a condition in which the pump will begin to cavitate. The hull isn't applying enough pressure to the surface of the water and the intake is too close to the surface of the water, or the pump is drawing more water than is found in the column directly in front of the pump's intake, the laminar flow becomes turbulent, Simply put, (very much over-simplified) the water next to the hull is moving as fast as it can, the pump needs more, a vacuum develops, and your impeller dissolves amid a bazillion micro-vacuums, result - your boat basically just sucks... literally. Just grafting a PWC hull designed to feed the pump properly through a given operational envelope to a hull unable to operate within a parameter near that envelope is an exceptionally bad idea.
Could a jet tuffy be done? Definitely. But don't expect it to be as simple as hacking a 60 mph performance PWC off at the waterline, and gluing it to a hull that is much heavier, flatter, and designed for an outboard.
Just my 2 cents worth.
Some plan to stroll through Saint Peter's Gates, I plan to go through them at 150mph... backwards... in a screaming ball of flame, with a glimmer belt wrapped around my head, and a NOx button in my hand.