My plane is a little tail heavy and wants to climb when increasing the throttle. I have to trim in some down elevator. If i shim out the motor do i shim the top or bottom. If i shim out the top is that called down thrust because it will cause the nose to push down or am i backwards and its called up thrust because it pushes air up? Anyway what do i do if i do not want the plane to climb when increasing the throttle.