Taking On Water on Driver Side Under Floor Mat

[Sundown94]

Well, I'm back from a business trip and wanted to take a sec to provide an update on my leak. I went and boat "black adhesive silicon" and last Thursday. I removed the corner roof light and -- to my surprise -- found that the lightbar wiring travels very nicely into the truck through a rubber gromet. Also running through the same gromet are the wires for the corner light and it all looks very stock. So I got the ol' garden hose out and poured water all over the spot where the corner light sits. I made sure to drench the rubber gromet, etc. I looked inside my truck and there was no water coming in. :-( I spent about 15 or 20 minutes doing this and nothing. So then I thought maybe my leak is not the corner light, but rather the sunroof or maybe down by the wiring harness for the door. Still nothing. Is it possible that the water has to build up or collect somewhere first before finally leaking into the vehicle? Because I spent so much time spraying water on the corner light, I could not spend too much more time spraying down the sunroof (I ran out of daylight). This may sound really stupid, but should I open the sunroof and pour water directly into the channel? My goal is to see if I can actually find the source of the leak before slapping silicone in random locations all around my truck.