If "red" loctite is used, and you will never know until you get it off, you must use a propane torch. It was the only way I could get mine off. Try to keep the flame on the tube and not on the receiver as you can discolor the anodizing. Once it gets hot enough, it will come loose. I did not use a block of wood in the mag well, I wrapped the heck out of the receiver with soft cotton towels and then stuck it in the vice, you do not have to put pressure on the lower receiver, just tighten up the vice enough so that the receiver will not twist and have someone else heat while you do the twisting. You should'nt need a breaker bar, an 8 or 10" crescent or open end wrench should do it.