After the big rains stopped I was able to get back to solving the water leaks...
I removed the windshield trim pieces and found quite a mess.
The trim had a bunch of dirt packed in behind it and silicone sealant slathered all over. I scrubbed the rubber gasket with a brush and Dawn detergent then dug out the silicone and old hard factory caulking. The arrow points to the lower A-pillar seam which has a nice hole. The factory caulk was cracked and loose.
The upper part of the pillar shows another hole at the roof seam.
Both of these holes allows water to run down the inside of the pillar. I suspected this was the source of my leaks.
After scrubbing the gasket some more I lightly rinsed the soap sud off then took a quick peek under the dash.
WOW! Serious water intrusion with the caulk and sealer removed!
You can clearly see the water tracks along the dash/cowl edge as well as where the dash meets the A-Pillar/upper kick panel.
I didn't notice the rust staining on that bare metal until I was editing the image.
I decided to remove the black rubber caulking to see what was behind it.
As I suspected, there was another opening behind that caulk. This one is very near the corner of the windshield and where the a pillar ends as shown below where I poked my pick tool through it.
I went around the windshield gasket and scraped out quite a bit of dirt as seen below.
Because I wasn't able to replace the windshield and gasket, I took the RendNeckJeeper® route and applied clear silicone to the pillars and gasket then surface sealed it to the glass and body.
I removed the seats, carpet, insulation pad and the factory rubber floor mat to allow everything to dry out.
After allowing the silicone to cure overnight I doused the windshield with water and was rewarded with a wet floor...
The biggest leaks are landing on the E-Brake and brake pedals with other small ones at the kick panels.
My next step is to see about pulling the dash out, stripping the caulked seams and applying new sealer from the inside. I can't come up with a effective way to get sealant into the cowl so I'll cheat on this one a bit.
When, not IF, I get these leaks fixed I think I'll put together a FSJ Leak Guide thread that shows where the leaks are and how to stop them so others will know what to do.