I used a Craftsman 8 point socket on an impact. A bit of heat (mapp gas) and some PB a cycle or two before trying. This was after using my closest metric socket and rounding it off a hair. Had to hammer the 8 point socket of but it came out. Would be better off with a square socket but I was unable to find one. In any event, it'll put up a fight but nothing to be afraid of IMO.