JUST DO IT
Taking the boat out out on your own terms is where you start to learn how she handles and where the little things are that need attending. I imagine it'll take quite a while to get tab trimming down to a matter of instinct.
Regarding the intermittent tach & hour meter, could be grounding or poor terminal connections.
If you had high water at the ramp do you feel you could launch/retrieve single handed?
Does the cockpit self-bail OK?
Those canvas guys are $proud$ of their work.
Hour meters are a PITA. Mine only showed 987 on a 13 year old motor
If the tach is acting up, be sure and check the charging voltage when the motor is running. On a lot of motors the voltage regulator and the tach signal come from the same electronics box.
Trim tabs do take a little getting used to. I didn't notice what kind of switch you have. Normally they are dual rockers. If they are wired correctly, just look at the pair of switches as the boat. Don't think about which does what with what tab.Press down on the right front and the right bow will go down, etc.Press both rear switches together and the stern will go down and bow up. After a full day with a lot of running I can't remember where they are so I press the rear of both to bring them all the way up and start over. Experiment in the driveway and find out how long (one thousand and one, one thousand and two...) it takes to go from full up to full down and to make sure that they travel equally. I have learned that about 3 seconds of down on both tabs (front of the switches) is a good starting point for my normal cruise attitude. Don't over-correct. It takes a couple of seconds for the boat to level out to a new setting.
Rick, you asked about sodablasting so I went out and took a close-up shot (1.5" away from hull) to show the effects. The pits look large in the picture but but could be wet-sanded out. Wet sanding a hull your size would be a big task. Anyway, I just wanted you to see the "after" surface.