Let's back this up a bit.
Have you shot this gun yet ?
Does it cycle ?
If yes ... Are you going to use a suppressor ?
If no ... Is the gas port hole lined up ?
Line up the gas port hole to the gas block and run the air can test ! Once it works ,mark spot and drill new dimple in the bottom of the barrel in the spot of the screw. Only go a fraction of an inch, VERY minimal !