I did not rebuild the West Bend 82001 go kart engine because it did not need it. I did replace the rod bolts with 7/8″ long Torx bolts. I am not comfortable with the original 5/8″ long bolts. The Torx bolts are grade 8 just like the originals but they feel a lot more positive when I torque them to 90 inch pounds. I have run into WB820s with rounded out hex head bolts. They are difficult to remove.