[JohnB]

I think wedges can go either way, negative or positive. I am not an expert on them. The boat I am thinking of was an older 31 contendor with 225 4S yammies, and I remember looking at it on the trailer and the motors looked like these, tucked under the bracket. I think he installed something that when the motor were trimmed down, they would be in a neutral vs negative trim state.

The idea is that when the motors are trimmed all the way down, the motors will have a neutral trim, in that the cavitation plates are paralell to the water they are running through. The water coming off the back of that boat is not flat, it is angled up about 10 or so degrees, or at least it was on mine. I moved my motor up and down on that bracket serveral times, and played with the trim to get it right.

Obviously, start by running with the trimmed up so that the cavitation plates are paralell to the water. This is hard to do without 2 people. I used a camera to shoot pictures of where the water was hitting. The key is to get the height in the ball park, then dial in the trim. I would start by using a straightedge off the bottom to the cavitation plate, and mount the motors so the cavitation plates are at least 2"'s above that line.