Regarding drilling out the heads…. I need a drill bit the same diameter or bigger than the screw shaft, correct?
I'm concerned about damaging the rocker the bolt is passing through.
I'm going to Canadian Tire tonight. I'm gonna buy a few of things mentioned here and hope one works without damaging the bike or shock
If you aren't sure what's behind the screw, then it's probably best to not proceed. Normally there will be a washer, or enough clearance to use a larger drill like I mentioned.
If the screw extractor doesn't work, another possibility is to weld a bolt to the head of your screw. Any good/independent car mechanic could do it as long as they do exhaust work. I once had it done on a broken stud in the head of an engine. The guy charged me $20 if I remember correctly.
If the hardware is aluminium, then welding won't work. The close proximity of the heat could do some damage too, if not careful.