I believe that the OEM bushings are pressed in from the outside. The diameter depends on whether you are using 3/8" dia. hinge pin (drill rod). They will have to be reamed to a press fit to the bore. Use oil lite bushings. If you press them in from the inside you will not need a washer on the inside. The inner section is drilled for the 3/8" pin with a set screw to hold it in place. 01