This someone stripped 2 of the screws on the top (needles?) and super tightened the screws on the float bowls to the point where even PB blast, isn't getting them lose after a soaking for an hour.
For the float bowls I always use a small pair of vice-grips to loosen them, I never (and I mean NEVER) use a screw driver to loosen any carb screws (or screws in general) that I can get a small pair of vice-grips on. Just use the smallest pair of vise-grips (I have a tiny needle-nose pair) you can find and try them, they work great. I loosen the screws this way and only use a screw driver to tighten them, and not too tight at that.
As for the needles, I haven't encountered that particular problem yet, I'm sure someone will have a useful solution. Hope this helps and Good Luck!