Mark 3 and engine height

[skoskii]

Should the motors cavitation plate be just lower than the bottom of the transom or the speed tubes?

[nice.diver]

on my mk3 GR
the tubes on my boat "hang" lower than the center of the transom, so when the boat gets up on plane..(.tubes on top of the water.)..the transom is above the water surface.

you want your prop to stay underwater when the boat gets on top of the water.