Just use Burris Signature Zee rings and there is no need to lap them, the inserts center and align the scope just fine.
There is another tool that goes into each seperate ring. The ends in the middle are pointed and when the points line up, the rins are square.
I've seen those, but from what I can see they wouldn't work to tell you for sure that things are lined up. Try this: Take two sharpened pencils and lay them on a table with points touching. Notice that you can keep the points touching and move the pencils left/right to form an angle? Now, imagine that you could move the blunt end of the pencils up and down as well as left and right - points still touching, but the pencils are not at all in a straight line.
Now imagine if the ends of the pencils were cut square, then you can tell when they touch if they are lined up or not, so those pointy tools could be replaced with two pieces of round stock with perfectly flat, square ends and then you'd have a useful alignment tool.
Just Sayin'
Just a Shooter