Your prop must be seriously wrong. You shouldn't need much if any tab to get on plane. Drive tucked in, tabs neutral, keep it under 3500 rpm, roll on easy and it should jump right up. Once it rolls over kick the drive out "a bit" and you'll feel the boat loosen up. Play with the drive setting and feel the boat. If it feels "wet" and nose heavy, kick the drive out a little more. If it starts to hop, you've gone too far. You get into rougher water and start airing it out, you sholdn't be nose up too much when you come out of the water. I really didn't use the tabs in our Baja much at all unless I was in some big water and needed to keep the bow down.

I pulled the 454 out and dropped a worked and chilled 525SC putting out about 650 hp and it was hitting about 80. Started getting a little sketchy.

White knuckle ride!

Any updates on the new ride?

prop wise no. Local guy didn’t have any I could test. Gonna go through bblades rental program after I get some more info to give them.

I did change impeller and housing, all fluids and filters.

Was on water to get MPH and RPM to try different prop, and go figure mph gauge went out. Was still showing up to about 35 and wouldn’t go any more past that. So, I used a gps speedometer on phone and took video of that. Got about to 60 mph about 4600rpm. Any ideas where to check for mph gauge?

Clogged pitot tube or pick up

Update to some of the issues:
Boat started to die upon initial startup and couldn't hold RPMs steady. Swapped IAC and Temp Sensor w/ little to no change. PITA to get started and maintain idle, once it gear it does fine at idle, but now it really struggles to get on plane if at all. Boat now hits about 2500 rpm trying to get up w/ backfires every 5-10 seconds. Swapped cap, rotor, plugs, wires and new gas no change. Pulled out of water yesterday to dig deeper into the issue.

I did notice the drive trim limit insert 'celery stick' was on opposite sides, guess that could explain the initial struggle to get out of water from the beginning.

Turns out fuel pressure is low, high as I could get it was 23 psi. Calls for 42 psi. Couldn't find any leaks, getting a fuel pump and hopefully have it resolved by the weekend.

Swapped fuel pump, and adjusted timing. Running good now, still kinda slow out of the hole w/ two people and full tank. Gave it a good wax and changed the boat name decal.