I bought a Magpul handguard for one of my AR's. I accidentally purchased the midlength instead of the carbine length. I realized this as soon as I pulled the damn thing out of the box. Instead of returning it, I decided to put it on my .308. No big deal, right? What the fuck ever dude... Actually, It wasn't that bad. I just shaved and/or filed down parts of the handguard that didn't fit just right checking, time and again to make sure there was a proper fit. About an hour into this and not being able to see what was preventing the guard from dropping in, I (in my infinite wisdom and utter frustration) decided "hey, why not take the gas block off, install guard then reinstall the gas block?" So it was. Should I be worried about anything pertaining to the gas block and tube?