I have had my 70 for 15 years and it always gets wet inside when it rains. After replacing the windshield and caulking every seam and hole I could find it still leaked. About two weeks ago while trying to get my window lined up I took a good look at where the weather strip seals the top of the window. There is a 1/4 inch wide piece of chrome that is part of this weather stripping channel,were it meets the body underneath the drip rail. I took some clear silicon 50 year house caulk made a very small hole in it, maybe .040 then used a piece of mig wire to break the inner seal.
Caulked it in, removed the extra caulk.
You can't even tell it's there and not one drop of water in the car after three good rains.
I hope this helps someone else out.

I discovered the same culprit on my 70 model just a couple of weeks ago. I haven't repaired it yet, but my leak is at the exact spot you speak of.

Was yours on the left or right side? Mine leaks in at the passenger door.

I believe both sides were leaking, I repaired both just to be safe

Post some pics if you can. That would be helpful.

Don't really have a way to post pictures at this time, maybe one on the other guys can?