#1) your prop looks like crap. Dings and nicks on the leading edge will almost always make it cavitate like crazy. Borrow a good prop. Reworked Alum props are around $45-60.
#2) The cavitation plate (anti ventilation plate is the proper term) above the prop should be between 1" below the bottom of the hull (use a yardstick as a straight edge) and EVEN with the bottom of the hull. You are VERY deep with the motor, and the deeper you run, the more LEVERAGE the prop has to lift the bow (wheelie). Since you already got it clamped on, don't raise it up yet. The cavitation is the first issue to fix, and I point my finger at the prop for that problem.
#3) Move fuel tanks and batteries to the front of the boat until you get your weight balance figured out.
#4) Move trim pin to lowest position. I don't see much camber in the transom plate. A wedge may be needed, but gotta get your cavitation worked out first. You should be able to plane and run even if the motor angle is too high, but it will porpoise if it still needs a wedge.
I grew up in little boats with big motors, and you aren't running into anything we didn't have to work out on all our homemade stuff.
Worst one was a 9' plastic dinghy with an Evinrude 33hp Fastwin. Boat would sink tail first if it had no person in it for ballast. We only played with it for one day and launched it with people in shallow water holding onto it while a guy climbed in for a run. Was pretty fast. Hard to keep it in the water.
I got a '71 13 foot Whaler Sport with a hopped up Johnson Twin right now. Around 65hp. Short shaft, power trim. Stainless prop. THATS a fun dinghy.