Lol are you in advertising? You got my attention! I was going to direct you to Craigslist!
Adjusting the trim is a feel thing. You'll start all the way down and power up while going straight start to trim up and watch your speed. Just go up a little at a time until you see the speed start to drop.
My trim at max sped is a couple taps past 3/4 up with just me on board. Depending on where more weight is (and how much) you might trim differently. When cruising I typically trim up when larger wakes are heading towards me to lift the front of the boat,and then back down to cruise.
(FYI) when you get to the max speed, you might start to "porpoise". This is when the front of the boat lifts and drops like you're bouncing in a 65' Impala with hydraulics. Just back off the throttle, or drop the trim, or enjoy the ride. It's all a preference thing.
Good luck in finding that perfect "trim"!!!!!