nipple issue!

I've had issues with mine. I had to have 2 rear calipers replaced. How badly has the thread been rounded out?
 
Ouch, this happened when my mechanic tried to bleed my front calipers and I was forced to source some new ones in the end :worried:.

Luckily a guy was breaking a 225 and sold me a second hand pair for a steal, I also sold my old damaged pair to a guy on here for a decent price so he could repair them and double his money.
 
Recently had mine bled but my mechanic couldn't get one nipple on the front undone, he didn't want to force and strip it so not sure what to do. Could a break specialist sort this without having a new calliper.
 
Tree, if you heat it up a bit the metal should free up. My mechanic had the exact same issue and applied heat. Managed to save the fronts but not the rears
 
He had this heat ring thing rather than going at it with a blow torch. Got it round the actual nipple itself so didn't take the heat off the caliper. Seemed to work well!
 
Took my rears to a machinist, said there was not much could be done!
Just for the record do meg 225's fit?