I would weld in a receiver hitch and not try to use a ball on the bumper unless you plan on towing something as light as your lawnmower. They weld on between the frame rails on AD trucks, don't know about the 42.
Draw Tite makes a large selection.
http://www.drawtite-hitches.com/?OV...OVADID=2066031022&OVKWID=19879794522


~Jim