1986 Buick Century Custom 2.5L-4 "R engine": accelerator control cable popped off the throttle lever. Missing circular retainer & washer? Apparently rubber grommet which attaches to throttle lever tore & binded cable. I can locate a circ retainer from Dorman, but need washer dimensions, type, i.e. metal or nylon & rubber grommet which may only come with the cable. GM has discontinued parts...I tried cutting a rubber Holley throttle bushing to size. Lost 2 circ clips & metal washer in the engine.