DeepPenetrator

I bought a couple of xj's in the last couple of years. I've never owned them before. Both of them a 96 and a 98 had their AC systems removed. Both originally were equipped with it. I plan on putting AC back in one of them (the 98 most likely as the compressor is still in tact). However, I don't know why the AC was taken out of service for either of them. I want to make sure that the most painful part, evaporator replacement, isn't the issue. How do I test an evaporator to make sure it's still good if the rest of the system is missing? Is it a simple pressure test? How is that done?

Saudade

Was everything but the evap taken out (accumulator, condenser, etc.)? Were the ends of the evaps covered/plugged? How long has it been disconnected?

Either pressure or vacuum. Vacuum may be easier. A hand vac pump and some plugs. Pull a vacuum (as much as you can) and wait to see if vacuum drops. If steady after 30 minutes, It may still be good.

However, if the ends were uncovered, a lot of dust, moisture, bugs, who knows what may have gotten in there. You could try flushing it but honestly, I don't think I'd use it since you are going through the trouble to replace everything else. Same goes for the condenser if it's still there.

DeepPenetrator

The 98 has the condenser, compressor drier etc still there. They stuffed paper towels or the like into the open pipes.
the 96 only has the drier an the evaporator but they crimped the ends of the lines closed,

country2

If it was me I would pick one and say heck with it and go ahead and replace evap and while I had everything out the heater core too and go with new everything. Thats what I did to mine and yes it was a pain but if you can remove the seats it will make it easier but if like mine was the bolts will be rusting and won't come out. Still cold 6 years later.