i had one stuck as well, here is what i done.
Heat the carb up with a dryer and use a good fitting screw driver to loos it.
But as you said it has being ate away so now you will have to get it out with this tool i dont know the name but what it does is screw into the jet but with the direction opposite to the locking way so when you start to screw it in it will actualy start to loose the jet.]
Remember to insert this tool while the carburator is cold, then after that heat the carburator up and turn it "click" sound comes after and it will come out.
Maybe some one knows what tool i am on about. i am sure they sale them in hardwear stores it look like a drill bit by the way.
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