Took the 2150 carb of a recently purchased truck to rebuild it. Everything went smooth except for one of the idle mixture screws. Completely stuck. Didn't appear to be driven in too far since the other one was in about the same distance and came out easily.

After hitting it with PB blaster and letting it sit, I starting working it out with the largest screwdriver that would fit. Got about an eighth of a turn out when the head snapped off. Figured I'd disassemble the rest of the carb for a soak and deal with it later.

Got it out of the soak, hit it with some more PB blaster and tried using some needle nose vice grips on the quarter inch still sticking out. Thought I was making some progress, then the rest of the screw snapped.

So now I have a broken idle screw, flush with the carb and pretty well stuck. Didn't get much backed out as I can still see a tiny bit of the tip on the other side inside the carb.

What are my options here? The way I see it I can:
A) leave it be and do without any idle adjustment on that side - truck ran OK before I took the carb out. Had a tank of bad gas when I got it so I figured I'd rework the fuel system from tank to manifold, which so far has been a good idea - lots of rust, cracked tubes, and unknown gunk.
B) get a small left handed bit and try to drill it out without messing up the threads - not too optimistic about it working itself out at this point though.
C) new carb - problem here (aside from money) is that the original did not have a tag so I'm not sure exactly which 2150 version to get as a replacement.

 

I think you've covered all the options. I would advise against (A). If you can't get it out with a left-handed bit (likely, as you suspect), replace the carburetor. As long as you target the same year/engine, you'll be close enough.

 

I agree with fmc400 . If nothing else , buy a used carb , take 2 and make 1 . You need to be able to adjust both sides , IMHO .

 

Try some heat b4 you give up. Wont hurt. Might work. Take a SHARP center punch and punch it b4 you you start. Drill it then heat it. Worth a try