I looked all over the net to try and find out something that I have wondered for a long time. If you are in the military (Army, Marines primarily) and you are in an infantry unit, are you allowed to add anything to your rifle if you were to buy it? What about paint it? Or do you have to be assigned optics, flashlights, etc? What if you were to buy an RIS System? Would you get into trouble if you were to put it on your weapon? Thanks guys!