Did the retainer pin break just past the thread? That's what usually happens. Figure out where the end of the pin should be in the carrier, and drill a small hole at an angle over it so a piece of stiff wire like a thin welding rod or a piece of clothes hanger can be inserted to push the pin out of the hole. It beats destroying the carrier, and doesn't weaken anything.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!