[W126 Coupe] Speaking of leaks...

[Josh Allen]

Since we're already picking our member's heads about leaks, can anyone 
speculate or suggest a course of action for me?

On my SD, I have had a dripping leak directly onto my left thigh when 
driving in the rain.
I finally got around to pulling the front headliner apart while waiting 
to meet another owner a while back, and found that the water was coming 
in along the windshield, just above the steering wheel, and had been 
running across the headliner to the joint at the top of the A-pillar and 
dripping out.

My question is about the best way to seal the leak around the windshield.

I haven't been able to confirm it, but there appears to be no gasket 
around the front window, but rather that it's sealed in with the black 
goop more common on later model cars. 
If this is the case, how is the trim affixed, and how best to get in 
there to either remove and replace the windshield, or to add more goop?  
(I have a tube of 3M urethane window sealant that I'd picked up a good 
while ago for a project that didn't happen.)

Any thoughts?

-Josh