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If you're seriously considering rebuilding your old carburetor yourself (which I would recommend), you may want to pick up this book: Carter Carburetors by Dave Emanual, ISBN: 0931472113. Available at Barnes and Noble (http://shop.barnesandnoble.com/booksearch/isbnInquiry.asp?isbn=0931472113), among other places. 

Granted, it's got a lot of info you won't need unless you want to tune your carburetor by grinding and replacing parts, but it does provide a good introduction to carburetor theory and operation, as well as the specifics of Carter models. On the other hand, you can get 90% of what you need from the shop manual. If you don't have the shop manual, BUY ONE. It's the best money you'll ever spend on your car. They pop up on eBay all the time for ~$15.

Before you start tuning your carburetor, there's a common misunderstanding that needs to be addressed: the "idle screws" on the front of the carburetor adjust the amount of fuel/air mixture that is pulled into the carburetor bore at idle. There are 2 things to note here:

They don't adjust the fuel/air ratio; that is predetermined by the size of the idle bleed vents and the idle tubes.
They don't adjust the idle speed directly. This is merely a side effect of adjusting the amount of fuel/air mixture that is drawn into the carburetor.

Rebuilding tips:

Completely disassemble the carburetor and clean it before you add the new gaskets, valves, etc. in the rebuild kit. I mean take out everything that will come out (shafts, plates, valves, etc.) before you clean it. A lot of these older carburetors get gunked up in places like bleed vents. Merely replacing parts won't address this problem; you need to clean the carburetor. You can buy a gallon of carburetor cleaner complete with a parts basket at your local parts store (or Auto Zone, anyway) for about $12. Soak it overnight, and put it back together the next day. I generally scrape off all (or most) of the outside crud with a wire brush before I soak it, then blow everything out with high pressure air when it's done. Blast air through every hole you can find (needle valves, float valves, bleed vents, etc.). If you don't have a compressor, a bicycle pump will do (but your lungs won't). A little dirt in the wrong place (e.g. idle bleed vent) can cause big performance problems.

Don't polish the throttle and choke shafts aggressively to clean them. All you need to do is take off whatever varnish and/or carbon may be on them. If you take off too much metal, you'll have a sloppy fit, which will create a vacuum leak and screw up your air/fuel ratio. It's also possible that the shafts could be loose because the holes are worn, but that doesn't happen very often with the AFB because the throttle body casting is so thick. 

Don't forget to clean the choke (including the piston). It frequently clogs up with carbon, so your choke sticks. If you want to go whole hog, add an electric choke.  See here for more information.

Lastly, the rebuild kit will often have different specifications than the chassis manual for things like float drop. I always go with the manual.

Questions?  Answers?  Comments? Please send them to . Thanks.