W123, SVO/WVO parts

I've followed along numerous posts on this subject and followed instructions where I could, but my car is still a DOG.

I have performed all of these fixes yet not realized much difference:
-Cleaned banjo bolt
-Replaced air/fuel filters (many times)
-StarBrite anti-fungus fuel additive
-Replaced some vacuum connectors (not the 3-ways, just the small pieces - I'm poor, but working on it)
-Replaced brake booster vacuum line - it had 2 broken nipples.
-Replaced vacuum switch levers (the two plastic things on top of the valve cover - whatever they're called)

Have 82 240D ST sedan and am looking for a reliable, inexpensive and certified classic MB mechanic in the area who might be able to repair my A/C system....have replaced condensor several times without luck...works for a day or so, and then konks out....no leaks evident...compressor appears to be working properly....just can't get it right.....thanks.

Have a nice 1982 240D four-speed, standard sransmission (floor shifter) with about 140K miles on it. Recently experienced big problem with shifting from one gear to another. Thought it was a bad shifter and secured a replacement assembly unit which has been installed this past week. Have replaced all external bushings (except for white plastic bushing inside actual shifter unit)and everything appears to be tight...not loose. Can replace internal shifter box bushing but I don't think this is the problem.