I want to change out the wood stock and fore end for a fiberglass one on my 870 Police shotgun. I know that I need to buy a fore end wrench from Brownells for the fore end swap but how about the stock? My buddy says that the Remington stock tool looks to him like a 3/8? drive socket set with a 9/16? drag link socket. Has any one tried this and if so is this the right size? Thanks