Some Ingenuity Needed

[TownsendsFJR1300]

Extractor sockets are the go for removing rounded bolts. I bought a set years back for about $20, use them heaps to remove worn bolts in harvesters. Use some heat to soften the loctite. Most good tool shops will have them.

Unfortunatly, the stock bolt heads for the discs have a "rounded" edge, brand new. The extractor may have a hard time grabbing it but would be worth a try...

Any decent machine shop should be able to pluck it for a minimal amount too...

 

[FinalImpact]

The rear is flush and countersunk which is the part in question. Thus peening into usable shape, drilling it, or welding a nut to it are the options. Because SS and/or coated with something, expect it to splatter a fair amount w/out the proper wire if welded upon.