I made a custom receiver hitch for my S-10 many years ago. I wanted the receiver to be hidden behind the license in the rear roll pan. I used a late 70's monte carlo spring loaded license plate holder to hide it.
2 mounting plates, a cross tube, a few gusset plates, the receiver tube with reinforcement ring, and spring-loaded chain anchors.
took one hour to measure, about 3 hours making the parts, then it took about 3 hours of fitting, and about an hour of welding.