On The Subject Of Rust...

I also noticed during the last rain that my glove box was filled with water (first time this happened). Where you think this is coming from? Does the cowl vent have a tendancy to rust out on XJ's like old Mustangs? Just curious. I also have to pull my windshield and get a bit of rust that's in the lower RH corner...dunno how that's going to work out, never pulled one of these new style windshields (with the rubber tape stuff...)

Sequoia

It's my understanding that the cowl vents on XJ's do rust out, especially the area under the fan blades. My 87 never went there, but rusted at far left, underneath the wiper mechanism. But the usual spot on the right would, I think, be below the glove box, so I would suspect the windshield.
It's also not uncommon to have windshield leaks, which can dump water anywhere. Yet another place to check is at the top, because a leaky roof rack mounting can put water all sorts of strange places.

It's difficult to pull a glued-in XJ windshield in one piece, but it can be done. I'd wait until I needed a new windshield anyway, because it's really easy to break it getting it out.

Actually while my windshield ins't broken, I have this annoying chip where the previous owner somehow knocked the rear view mirror off along with the glass! So I think I'll just replace the windshield when I find a deal, then fix that rust spot (actually, the window channel repair there is one of my specialities...I've had to do it in all my damn cars!)