Classic or LMC has the correct rubber ones. I was told the ones with the metal were for a car (don't know) I believe that Classic has the correct ones in rubber. By the time they came , I had a local machine shop (car guy) make them out of brass. If you do, have them put mushroom top on them like the rubber ones. It make assembly easier. The rubber one were the same dimentions as we had miced them. He used 5/8" brass pieces he had and turned them down and then drilled them. Works great