Qsc primary

I think you mean you stripped out the allen head so you can't remove the bolt. If so, you will have to drill out the head until it can break off, unscrew the threadded section then get another bolt to replace it.

If you stripped out the threads, you will need another base section. If you drill and tap that, it would be out of balance due to the larger steel bolt would be heavier than the aluminum it is replacing.

The threads aren't stripped it's just the head yes you are correct

If you can get a dremel with a cut off wheel in there you might be able to cut a groove in the head and use a flat head screwdriver to spin it out. Hardware store should have a replacement one. If not, let me know and I'll drop one in the mail.

I got the bolt out. Does anybody know what size these bolts are?

I never checked the threads, and don't have any here to check for you. Still waiting on clutches to get here. Take another one to the hardware store with you and they will match it up.