Make from al alloy 6061-t6, per qq-a-250-11; housing to be chem filmed before insertion of helical coil inserts; chem film per mil-c-5541 class 1a and5124; drill 0.089 inch through csk 82 degrees by 0.13 tap 0.112, 40 unc-2b thru; drill 0.1200 through 4 places; drill 0.277 through cbore 0.44 flush to 0.010 below surface 2 places; drill 0.0781 by 0.27 plus 0.030 inch, ream 0.0942 plus 0.0010by 0.17 plus 0.030; drill 0.277 thru; drill 0.1200 by 0.270 plus 0.030 deep, csk 120 by 0.16 dia.; drill 0.070 through wall csk 82 degrees by 0.100, tap 0.086, 56 unc-2b through wall far side