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If everything is stock and hasn't been worked on before don't turn on any screws just yet. It's probably been a long time since your O2 sensor was changed. If it has change it now. It would be a good idea to check your computer and see if there are any codes logged in it. Make sure you have a good ignition system, plugs and wires should be looked at. After these simple things there are a couple of little more complex things to check out like base voltage on the TPS and M/C solenoid. A rebuild really consists of nothing anyway, so checking systems out one at a time until you figure out the problem is the way to go.
I agree with Justin. That isn't to say that your carb doesn't need a rebuild, but on these carbs, there are a lot of other things that can make it run poorly.
One other suggestion is to redo your vacuum hoses. Wen I finished redoing mine, I was shocked at how much better it ran. This isn't a trivial job on these, but the results I have found to be worth the effort.
That should take care of most of the problems. Since the carb
is in a closed feedback loop most of the time, it should be able
to adjust itself to the best case...
Get a dwell meter to see what the metering of the carb is.
It should be within 30-40 range. Since your's isn't running well,
with the meter, you can see where it is and where to go from there
if the charts don't help you as much...
The TPS (throttle position sensor) located on the driver's side of the carb, can be a big source of problems. If they get gritty, or sticky, the voltage will get out of whack and feed bad data to the computer. It's essentially telling the computer how far the throttle is depressed and reacts with the proper air/fuel mixture. If it's smelling rich at idle, I'd suspect it (along with the 02 sensor). It's a 'system' where all the pieces interact. There's no real performance tweaking that can be done (aside from the secondary air valve and hangers) since the computer is going to keep the a/f ratio where it's supposed to be. If it turns out to be the computer, they aren't that expensive, and overall, it's not a bad setup when it's right. You can also get a performance chip for the computer, but I don't know if they're worth it. You may need it to pass emissions, so I'd check on that before yanking it all out.