I wish i could provide pictures of what I did, but I don't have a camera. I shortened the LOP on my mossberg maverick 88 by one inch.
1. Take off the recoil pad.
2. Take the stock off the gun. ( duh )
3. Mark where you want to cut with first a pencil, then a sharp knive or razor, just to give you a guide where to cut.
4. I just used a hacksaw, but if you have access to a table saw, use it. The cut will be cleaner, easier, and quicker. But my hacksaw worked just fine.
5. Sand the cut down and make it pretty.
6. Drill new holes for the screws for the recoil pad to go onto.
7. Install stock on shotgun and install recoil pad.
8. You may want to cut and sand the recoil pad to fit also. I left mine as it was, because I only cut an inch off the stock, so the bottom of the recoil pad is not much bigger than the stock itself.
Let me know if I can answer any more questions. Good luck!
O and yes I'm glad I did it and it came out nice. It fits me much better now.