Trim tab pumps
 

Does anyone know how to change a Mercury power trim pump to a trim tab pump, or how to adjust the pressure?

If it's the style with the plastic resevoir I'm almost positive they're the same. The only thing that may be different is the valve body between the motor and the resevoir, which would affect the speed. There is an older style pump that has the metal resevoir (same dia. as the motor) and it's a lot slower, but again the only difference is the center valve body portion.

That is what I am trying to find out, is how to change the pressure applied to the tabs. Thanks for the info that is what I thought too.

It will work fine. Just remember on a drive the high pressure side is up, on a tab you want to reverse it. The blue wire runs the motor in the high pressure direction. I you do want to adjust it there are two relief valves visisble when you remove the resevoir. they have a lock nut on them, just loosen and turn.