I've read that the mixture screw is supposed to be covered up by a cap from the factory. Is the screw supposed to be recessed into the body of the carb? Or do the cap and screw stick out a little bit. Not only is mine worn a little but I'm starting to wonder if it's even made for this carb. When it's turned out 2 and a half turns the screw protrudes out from the carb body about an eigth of an inch or so. I also noticed when rebuilding the carb that the tapered end of the needle and the hole it goes into didn't seem to match up. The screw seated before filling the hole if you can imagine what I'm saying.

It sound like you have the wrong idle mixture screw in your carb,with it turned out two and a half turns it should still be recessed because the plug that covers it from the factory fits flush with the outside of the carb when its installed.

Well by some miracle I was able to purchase a new mixture needle from the dealership (apparently they are rare, at least that's what the grumpy guy at the parts desk told me). I installed it and it seated at the same place that the last one did, still sticking out of the body of the carb. It didn't change anything. However just when I was about to starting cussing the stupid thing I found the vacuum leak that is causing all my woes. It was at the bottom of the rear part of the intake manifold. I don't know why it didn't manifest itself last time I did the carb cleaner spray test, but this time it was clearly the problem. So, any tips on redoing the intake manifold gasket? For example, do I need new bolts to replace the old ones? Let me know if there is something that I should know before making the same mistakes that others have made. Thanks.
And as for the mixture screw sitting so far out of the carb, I'm not sure what the deal is there the only other thing that I can think of is that maybe the spring on it is too long and the screw isn't really seating, I'm just compressing the spring until it won't go in anymore. That's easy to find out though. I'll just take of the spring and be real gentle.