A shot of my safety chain gusset template - copied off of another hitch.
Had to grind of the mess left by the PO on the bottom of the frame rails - He had some 1/2" flat bar welded on for his bumper. Note: grinding upside-down = not fun. Face shield or asbestos face required.
1/2" flat bar plug welded inside the tube to be drilled and tapped - grinding the plug weld flush