Here is my hitch that I fabricated. As previously stated, the key to a strong hitch and not stressing the frame is to distribute the tow load as far along the frame rails as possible. Mine is about 4' along the frame rails, fastened in 6 spots along the frame via the removable brackets shown in the second photo.
BTW: You can get a non-commercial status with your Class A license in CA. I hold a CA Class A with doubles/triples endorsements but for the last 10 years have been rated as a non-commercial driver, which means no medical every two years. You can submit form # 546, "Health Questionnaire" in lieu of the medical exam, every two years. I was initially concerned I would lose my Class A commercial license but the last update for my license remained unchanged. I believe you would still have to receive a full Class A with endorsements first, along with the initial medical checkout but subsequent updates (every two years) use the form above. I've never read anything about this option at the CA DMV, so maybe I just slipped through for the last 10 years but if you have your Class A commercial license already, try it.
NOTE: That is not the frame that is notched for the bracket. It is the sheet metal that the underbelly is fastened.
