You need to remove the existing recoil pad first. Look at the but end of the stock to see if it is solid or hollow. Most likely hollow. Then, look to see where the recoil pad attaches, after you cut, you may not have enough material to reattach the pad. That means you would need to use a slip over type. I successfully cut the composite stock of my mossberg. I used a horizontal band saw, no frays. I did however find a replacement stock ready to order in case i screwed it up. I attempted to get a gunsmith to cut the stock but i couldnt find one that would cut the composite.
"teal, teal, albino teal....wait, those are seagulls...take em.
wait till they line up and cross, 1 shell 2 birds