I don't see the rear frame bob as a problem. It's not un-doable if somebody wanted to go back to stock in 40 years. To someone that works with metal all day re-attaching the rear frame section to as factory condition wouldn't be difficult. Thing is though, the bumper corners are plastic. Nobody makes them anymore. Plastic doesn't last forever. It doesn't last very long at all in the grand scheme of things. Therefore a pro quality rear bumper replacement makes the most sense to me.