Any manufacturer's telestock will work on a Colt lower, as long as it is mil-spec. It is not hard to change them out, but a telestock wrench will help to tighten down the lock ring. I would recommend using a little loc-tite on the ring as they loosen easily. It is possible to use a small pipe wrench and a rag to tighten the locking ring, but be careful, and use loctite. You will have to buy the telestock as a kit, as you will need a new (different) buffer, spring, and receiver extension. Also there have been some issues with the flare at the front of the receiver extension and the buffer retainer (the little metal pin and spring holding the buffer in the tube), but with common sense and a little dremel work, you can always get it to work. Just think about what you are doing or find a friend who is mechanically inclined to figure out what needs to be done.