I would build a pressing block to help with removal of the butt stock. a piece of 1/2 inch plywood and a couple of 2x2 blocks. Bolt with carriage bolts, the 2x2's to the plywoodsuch that they border the butt stock just behind the pistol grip, just in front of the nose of the butt stock and along the comb at the top of the butt stock. I then use a 1/2 or 3/4 inch adjustable pipe clamp to apply pressure to the forward end of the plywood and the receiver. Tension the clamp and rap on the plywood form with a large rubber mallot. Don't try to force the clamp to do all the work.. Warm the stock and receiver with an electric heat gun before attempting removal.. This is quite common in older weapons and some high end shotguns that have press fit buttstocks. In the '97 I'd bet on dried oil and/or rust. Also possible that in the process of repairing a crack at some point the butt stock was accidentally glued on!! That would definely qualify as a worst case scenario...good luck from the gunnut69