Seems like I saw a universal tow bar at Harbor Freight last week. But if it's the kind that locks onto the bumper, I wouldn't trust it. I almost lost an early 70's Buick Centruy using one of those years ago. I've been thinking about having a bar made that would bolt onto the frame of a bus and alow it to be towed with a standard Beetle tow bar . . . but thinking about it is as far as I've gotten. I haven't figured out wheather or not it could actually be done.
