The kingpin bushings are BOST-BRONZ oil impregnated sintered bronze bushings part number FB1012-6. These are the equivalent of my FB1012-6-841 bushings. The top one was not too bad but the bottom one is cracked and wore out at an angle due to the bottom hole of the fishmouth tapped at an angle. If I had not been able to fix the bottom threaded hole I would have used one of my FB1012-6-DELRIN bushings on the bottom because it will tolerate quite a bit of misalignment since the plastic can flow a bit. I will use FB1012-6-660 bronze bushings top and bottom because they hold up better than the 841 sintered bushings.