i just dug around in my garage and found my old spare shifter, it still had the gasket and two of the original bolts. You are correct, M8 x 1.25 hex socket head. length was actually 30mm.Okay. I ran into a snag. I didn't keep the factory bolts with the shifter. I was able to do some digging and found that the bolts are M8 x 1.25. I did not find a definitive length listing. Length will likely be 20 or less.