Aluminum alloy; qq-a-225/8, temp t6; 8.250 in. Lg, 6.000 in. W; 2.000 in. Thk; 0.753 in. Diameter hole centered in edge and running 6.000 in. Through width; hole located 5.250 in. From hole center to one end; one 0.125 in hole drilled through face of stop and connecting with first hole 3, 000 in. From width end