It is really only necessary to lap the bottom half of the rings. The top will "find" the full contact point on the scope, unless it is really out of square. If you lap the bottom half of the ring to the "full contact" point, make sure the two halves of the ring aren't touching each other before the required torque is reached. If so, you will have to machine a little off of the "foot" of the ring. And don't use Vaseline on the inside of the ring - you will be inviting slippage on hard recoiling guns. The stuff to use is the rosin sold in Brownell's - apply it sparingly with a Q-tip on the inside of the bottom ring. Good luck. Roskoe