Grinding recoil pads is a job most anyone into guns will be called to install. My system is so simple and you don't need a 12 inch disk sander. Use a 3/8 high speed drill to turn a 5 inch flex disk. If you have a drill that will try over 2000 rpm's you can grind pads quickly. Start with a 80 grit disk and go up to a 150 grit for final finish. Masking tape with a couple of laps around the stock area first for about 1 1/2 inches of the area. Hold the hands up against the body and use your legs to move the disk around while using a light touch with the disk angled up at the rear area of the disk to keep from cutting in to quick. Practise, practice, and then practice again!!! Once you have this method down you can grind a pad before most people can get a jig setup to hold a recoil pad. I grind all recoil pads with the stocks on the metal parts. The weight helps and allow you to rotate into any angle to make the grinding very easy. Cover the metal parts and the clean up is quick. I use a bandsaw with a fine tooth metal blade and a guide to keep the pitch with the stock cut square where the pad is mounted. I am working on a PDF file and will post it later. 
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