There was a campaign for Us GM Technicians to install the cables on the engines except for the 1969 big block high performance L72. My car came with the heavy duty mounts. The tall pads were used on the big blocks so the oil pan could clear the steering arm and not rub. The replacement mount have the U shaped locks on them. This prevents the engine to lift and jam the steering wheel locks, throttle linkage, and column shift automatics. NICK L72