If the requirement is to have enough grip on the bolts' hex heads to stop them from turning, then I don't think 5200 would be good enough. 5200 has alot of grip, but it's still a "soft" material when cured, compared to epoxy or fiberglass resin. So if your intent is to glue the bolts back in place, I think straight epoxy, or an epoxy + short fiber mix would perform better than 5200.My fuel tank has a fiberglass top with a stainless inspection plate held down by 8 nuts. The studs for those nuts are really bolts that were glassed in place from the underside of the tank. Two of those bolts have broken loose. Since the heads are inside the tank they are inaccessible once the cover is on so I won't be able to tighten those buts. Reglassing them would be pretty tough. My plan is to 5200 them in place. I want something that will not break loose.
I am having a bit of trouble visualizing your requirement If you can give us a bit more info, maybe there will be better suggestions.
Good luck.