I have a Rem 870 Super Mag. I want to convert it to a tactical gun but change it back to a bird gun if needed. I want to install a mag tube and maybe a different stock. I have read you have to grind down the detents in the mag tube to install the longer magazine tube. With that done can you change it back to hold just 3 rounds. I have read mixed reviews on it and no one has really given me a good answer. I could buy me another Rem 870 but I already have all the parts to change it to a tactical shotgun. So I thougt about just swapping it out and then if I wanted to go Dove hunting I could change it back.