1.
Remove the grip screw and lock washer from the grip of your
rifle. Remove the grip. Mind the spring and detent for the safety as they may bounce out
as you remove the grip completely.
2. Using a 3/32" Hex wrench, screw in the tension screw from the hole exposed by removing the grip.
3. With the upper and lower installed, place enough tension on the screw to allow for a snug fit between the upper and lower. Too much tension may cause the upper and lower to be too tight making it difficult to push the rear detent pin.