This file should work well for the linked keyhole hangers, but may not work with other brands.
Depths to cut the pockets are listed on the file. If you use a 1/4" bit the inner pocket will not be selectable as a pocket cut and must be cut using inside cuts only.
There is a "T" shaped guide for help with visual placement. Simply align the top line with the edge of the workpiece and the vertical line with your placement mark. The "T" is exactly 2" wide and 2" tall and places the cutout 1/4" from the edge of the workpiece. There are also two 1/8" guide circles that can be used to locate pilot holes for the screws if desired.