[McGillicuddy]

You have 2 primary problems:
1. The motor is much heavier than the hull was designed for. Great motor, so adapt or go smaller, losing top speed but gaining handling. This could be unreasonable so go with what you have.

2. You have the wrong propeller. This is workable.

You may have an 3rd problem, that being the height of the motor.

Your boat was designed for a 300 lb motor. Yours weighs around 435.

If your highest RPM is 5000, you are way over-propped, meaning your props pitch is too high by about 3 "inches" or more and/or the shape of your prop is likely wrong also.

You need to tell the gang everything about your propeller. Make, model, diameter, and pitch. As well as what it's made of. Also what your maximum RPM is at wide open throttle when you have a pretty full tank of gas and what you would consider a heavy load. Are you're batteries astern or under the console? You'll probably need to place them as far fore as possible.

Also have a look at how high the anti-cavitation plate is relative to the bottom of the keel (use a straight edge with the plate trimmed parallel to the keel. That plate needs to be at least an inch and a half above the keel. Once you get the rpm and right type of prop, you can tweak the height so the plate is visible when running at plane. Some guys with 4 strokes and heavier 2 stokes have their motors mounted higher.

Armed with that information we can help you out.

Without that knowledge its a crap-shoot.

I will tell you right now that you will likely want a 4 blade prop or a three blade designed to lift the stern.
A lot of this info is redundant so my apologies.
Good luck and keep us posted.