I've put on the DPMS's before. The epoxy seems to hold really well. The first one, I just used the epoxy. Then I had an upper built and the builder put that tube on it for me and drilled it and tapped the nut underneath and installed multiple allen head screws, so it could be removed easily. MUCH better idea. That is how I do them now. Sounds like Scott may have figured out a better product. I'd also like to hear what he is using now.