I don't think you explicitly said, but I'm guessing the compressor isn't coming on. I'm not very familiar with your particular vehicle, but I wonder whether a low refrigerant charge could be causing the problem. After 22 years--especially if the A/C has never been touched-- it's very possible that i...

If the LP hose has a major leak, I'm pretty sure there won't be any refrigerant left in the system. But to be safe, wear protective goggles anyway in case refrigerant rushes out under pressure. You definitely don't want any liquid refrigerant in your eyes.
Let us know how it goes.

If there is zero pressure in the system, there is nothing to recover. I would go ahead with replacing the leaking hose, as well as the receiver/dryer or accumulator. Then evacuate and recharge according to the refrigerant specification on the under-hood decal.

The low-pressure-only gauges that come with the refrigerant cans are notoriously inaccurate and unreliable. These cans, known as "death kits" in the trade, often contain refrigerant and sealer. You definitely DO NOT want any sealer in your A/C system. Trust me on that. To get a better hand...

Oh, and I forgot to mention that it is normal for both the LP and HP to be close to the same when the system is off and that they'll roughly equal the ambient temperature.

Just a thought: It's possible that the system had sealer in it at some point. Sealer can cause all sorts of long-term havoc with a mobile A/C system.

I don't think you mentioned whether it's cooling. But based on your higher than expected LP reading (at an unknown engine RPM and ambient temperature), I'd bet vent temps are rather warm. Since it's impossible to tell from pressures alone whether a system is properly charged, I think I'd start be re...

Yes, looks like a parallel-flow condenser to me, too. Good! Upthread, you mentioned that the HP dropped quite a bit when spraying the condenser with water, suggesting insufficient airflow across the condenser. Since you installed a new electric fan and we assume that it's working as it should, doubl...

I'm trying to understand what the problem is, but I'm a bit confused about your comments concerning pressures, among other things. So, yes, I agree with Cusser. Start by having a professional A/C shop diagnose it. They'll have the training, experience, and specialized equipment necessary to make the...

I agree with Cusser. Your system was designed to work with R12. Converting to R134a is always somewhat of a compromise. I wondered, too, whether you replaced the original tube-and-fin condenser with a more efficient parallel-flow condenser. If not, doing so might help it cool a little better with R1...