I put some Sevigny sights on my 34 and I used a small amount of blue loc-tite. After about 700 rounds my f/s came off and was lost. I have a new one and I am about to put it on but started thinking that maybe I should use red loc-tite. What is your opinion? Also, I noticed that it says that loc-tite is not to be used on plastic, which the sight is. What have you guys used on your sights?