Mine has factory electric "trim-a-just" from Berkeley, but basically the same difference. I have only had to put it in the down position once, otherwise I am about neutral or trimmed up for some rooster tail. I have taken off from a dead stop trimmed up just to watch the geyser form when I nail it but every boat is different. Just start with it approx neutral and feel it out from there...
How big of a boat and what king of power is it making?