Wal-Mart just got a synthetic replacement stock and fore-end grip that is painted in Mossy-Oak. I want to get it since I use my 870 for Turkey and because I like the way they look. My question is this: The front grip does not have the rails installed that slide into the frame. Am I supposed to pull the rails off my old grip and use those and how hard is that for a non-gunsmith to do? I didn't open the package or anything so I don't know for sure if it comes with the rails or not.