I have an 87 civic dx with a d15a2 motor. I recently failed smog because the idle was too high (~1.1k rpm). All other numbers passed, though HC was very close to fail at 15 mph (1 ppm off).

I tried adjusting the idle speed myself but I created a vacuum leak or opened up a throttle/passage too much (I played with the idle adjustment screw, throttle stop screw, and another screw similar to the other two). The rpm now doesn't fall below 1.5k. I have a few service manuals (helms, hayes, chilton's) as well as an 85 crx dx parts car with a similar, possibly identical, carburetor. My question is this: should I try to keep adjusting the idle with the carburetor?

I've taken this Civic's head off, before. I've yet to disassemble a carburetor, though. I'm also considering the following:
1. swap carbs with the CRX
2. take it to a mechanic or smog repair shop
3. get a remanufactured carb (this one has at least 30k, possibly 50-60k miles on it)
4. just sell the car (it also doesn't have working ac and I've had trouble getting that to work)

Any suggestions?