I’m at work and only glanced at your post, hopefully not repeating too much. I noticed right away what Chris had already suggested. The strut is too high and should be right against the ski, that is probably causing the hopping issue. I also have no issue running the 1440 that Mark preps for a JAE 12, great prop and always launches. I don’t think you need to mess with it. Is the engine broken in? It takes about a gallon of fuel while running rich, and keeping the temp up to roughly 200 degrees for it to break in. You will be able to turn it over by hand (still difficult) it will wake up and starting singing once it’s truly broken in. I would remove the heat sink and run with just the head button if water & air temps are cool/cold. Adding a cowl to mine was a huge help getting the engine to build and keep heat. Began to run consistently, & helped keeping a rich needle to burn all that fuel and make rpm’s. I also will run mine on shore for a minute or more, helps warm up the engine before tossing it in, especially when it’s 60 degrees or less outside. A Nova 5 or 6 plug works great. Also 60% nitro if you have some. Head clearance set at .006-.008” is a must. I’ve never ran the Texan pipe, so follow Chris’s suggestions on pipe length. Good luck, I hope you get yours running well next trip!
Brian