Water in the bottom left interior storage compartment

[Rsvl-Rider]

I looked at a 1989 yesterday. We had a major rainstorm over the weekend and the car was outside, but all windows were up and moonroof closed. The bottom of the storage compartment behind the driver seat was wet. Not just damp but actually squishy wet. I had some bottled water with me and poured it into a rear glass seal separation that looked suspect but could not find an interior leak. I was not able to wet-test the moonroof but I suppose that is possible even though the headliner is pristine. There was aso dampness in the right rear (opposite) corner of the trunk. Connected, or separate issue? I don't know. Anyone with a similar experience or some tips to share in tracking this down?

 

Thanks