Those ARC systems are great when they are in good shape. The air line connections are the weak links, if the o-rings or seals in any of them wear and leak too much, the compressor will run too much. The system is very reliable other than the leak potential after 10-20 years. The rear height sensors have a joint in them which pivots, it's a metal ball/socket design. If that gets worn from corrosion, same thing from 10-20 years of age, then the sensor will be erratic in what it tells the module to do.
So if everything works but has air leaks, you can replace the shocks(all four for 95-98's, or two for 99-01's), with OEM NOS or equivalent Monroe's. The original shocks had electrical connections so internally they would alter shock valving slightly(like the 80's Turbo Coupe's had). I had the rear shocks watching on eBay, they ran about $60 each last I looked(I gave about $95 for a pair years ago).
If the compressor is allowed to run too much, that will kill it eventually, like all air ride compressors. Turn the switch off in the back to save the compressor if you hear it run too often.
To disable the system, just turn it off, swap the shocks, and disconnect the ARC module, which is behind and to the right of the radio(two connectors).
I'd like to have a spare ARC compressor, for my 99 that still works.