The installation is a bit of a pain in the arse. The barrel nut wrench that is supplied by Strike Industries is a weak POS. Yes, You do have to install the handguard onto the barrel nut before installing the gas block. The low-profile gas block I used has 2 set-screws on the bottom that secures it in place. The handguards have a place for the allen wrench to access the screws making it relatively easy to complete the installation. Depending on the type of low-profile gas block you use, it could be problematic. Strike Industries also gives you quality spacers to assit with barrel nut installation which I thought was nice. Once they're on, I absolutely love the feel and look. They are really light weight and the price is really good too. Hope this helps.![]()