Trouble with primary, any thoughts on a solution

Last week i pulled the cover plate for inspection, and while the spider looked good, rollers, weights, pins , buttons, spring all tip top shape, i did snap off a bolt on the cover plate:frusty: 2200 mi. on my m1000. It's been bulletproof so far. I've heard conflicting stories on whether or not these clutches can be worked on (they say you have to replace whole clutch. Can i not extract the broken bolt and replace it. And, if so, what's the best method of extraction without damaging the clutch? : PB blaster, heat, left handed drill bit, easy outs? And a replacement bolt would have to weigh in exactly to maintain balance, where might one be found?