Your Low side is the larger port, which at least on my '92 is facing the engine. The High side, with its 3/16" port is facing outward/upward. Another good general rule of thumb for almost all A/C systems is that the Low side hoses and tubes are the larger diameter in your A/C plumbing runs, and the High side is generally much smaller in diameter. You may also have an "S" and a "D" cast into your compressor housing near the service ports. S is for Suction, or Low, D is for Discharge or High side.The dampness you mentioned could be a leak from the front section of the compressor, but I've also seen some compressor weep for years and never take a dump or really leak any freon out, just a bit of oil from inside the system.
Not everyone makes an A/C compressor with these nice "notes" to follow, so the above rule about Line types and diameters gets you going in a hurry.
Lastly, if you had a blockage in your A/C system, generally the gauges attached to the system by the tech will show a vacuum or a near vacuum on the Low side or a very high reading on the High side. This is due to no freon being able to flow at what restriction point exists. Also, you can get a large amount of frost on the outside of a metal/aluminum tube if the clog is inside one of your visible metal tubes.
I know you probably didn't see the pressure gauge readings while the guy had your Monty hooked up, but here is a nominal reading for your R-12 system with everything working OK, and enough Freon left in the system before it leaks out.
Low Side-at idle to 1500 RPMs, Comp. clutch engaged, 30 to 20 psi would be great, 50 to 30 psi can mean trouble, like moisture in the system or an issue possibly with the Expansion valve at the Evaporator[sticking open a bit]
Could also mean a worn compressor.
High side-with ambient temps 90 degrees F and below, Humidity level not measured] and your condensor fan working OK-at idle to 1500 RPM, 180 to 275 PSI.
Mud, grass, crud in front of the A/C condensor will greatly affect this reading, as you're dropping off effiency for the condensor to get rid of the heat from the interior of the vehicle. Moisture in the system, worn compressor, low oil, clogging in one or more parts also affect the High side reading. Good Luck, I hope you get it solved in enough time to enjoy summer.