Gun Port Drill Jig directions (Cont'd):

"Pressed onto the head of the screw is a commercial straight knurled cap that makes a wrench unnecessary.

Two relief recesses were milled into the block to clear the ears and hinge section of the port lid so that it would sit flat on the bottom of the slot, when clamped."

Two holes for the carbide bushings were bored into the side of the block at .125" by .125" location, in relation to the slot and ears.

The holes are .118" ( 3 mm )diameter. Press fit to secure the bushings by friction."