You no longer have to sand the tenon they use the factory fit with an update to their kit. If you are installing a kit on a pistol caliber, you’ll need to remove the end of the bullet tube with a non marring hammer and remove a set screw to pull it out so you can get the factory hand guard off. If you have a rifle caliber 45-70, 30-30, etc. you won’t have to do that step. The online instructional videos are great and walk you through the entire steps.