Spiral tip extractors just expand the remaining piece tight into the hole, particularly a tapered pipe thread. I'd suggest drilling the fitting out just a little, soak with KROIL and do a little heating, then use a straight-flute extractor.
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
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