Here's a quick description of how to do that.
Lapping scope rings to optically center (or droop) you scope
Start by buying a small can of fine “Clover” valve lapping compound, and a three foot length of 1” aluminum tube (for lapping to a 1”scope tube. If you have a 30mm tube, good luck finding 30mm tubing...30mm scopes are pointless IMO)
Cut the tube into two lengths, one about 12” , and fit a short handle to that one...a small knob or a short bolt is fine.
Check the clamp surfaces of your rings, fix any flaws, and mount them where you'll want them with the scope in place. A tiny smear(what will fit on the end of a toothpick) of the lapping compound where each claw meets the rail will stop mount slippage under recoil. Lay the longer length of tube in the saddles with most of it ahead of the rings, and eyeball it's alignment with the barrel. You will virtually always see both off center and off axis misalignment. If it's really bad, you may want to swap mount positions or dress the fixed claws to reduce it.
Now smear about a peas size dab of the compound on the lower half of your short tube. Seat it in the saddles, and, tracing a figure eight with the handle, start lapping the rings. The figure 8 is important, you want the rube rotating both ways as you stroke the tube lengthwise in the saddles. A finger's pressure on top of the tube at the front will lap in droop, on the side to move the tube towards alignment with the barrel. After about twenty strokes, set the lap tube aside, wipe the saddles clean, and check alignment. Repeat until you get the guide tube to appear perfectly parallel to the barrel, or drooped ( about .010 gap difference Over 12” of distance, tube to a straight(not tapered) barrel is a good place to start) When the saddles are clean, occasionally check that with the scope in place and the upper rings on top, there's still a clamping gap. If you run out of gap before the tube aligns, you can either file the faces of the upper rings, or line them.