Changing my stock rearsets to Sato (Thank you @JimJr1945 ), and one of the the stock button-type allen heads were already rounded out inside. See #10 on image below. I'll be using the old center punch method, to work it loose first, then if that doesn't work, drill it out. No way am I going to replace those bolts with stock allen-head again. What are some of you using for replacements? All other bolts in this picture came out just fine.