Slight water drip inside cab - where the Hell is it coming from?

[D-Day]

This thing haunts me to no end. Due to the recent heavy rain, I've been reminded that I have a small leak up under the dash somewhere, and it's not the obvious culprit like the heater ducting, wires coming in through the door/weather stripping, and the windshield seal seems to be fine.

When I feel up under there, it seems to be on a steering column brace; and by feel, I think I can trace it to coming down this angled steering column brace that comes down at an angle from the upper dash, and braces on to the column.

I can not figure out for the life of me where this potential drop is finding its way in. Windshield seems fine, I've taped over the little holes above the cowling near the wipers (which took care of the water drip previously brought in by heater ducting), but this one I can't figure out. It's driving me nuts and making my driver side floor wet.

Any ideas? Past experience with drips and fixes, locations of problems? Any wetness in any part of the cab, and stories relating to are very welcome.