I am redoing my windshield Trim on the outside of the Windshield in my 1970 442 and noticed that when i removed the Stainless Trim around the Glass, there was a thin "Black Strip" inserted into the back side of the Trim....Looks like it may be Plastic??...very thin...Is this some kind of Seal Strip or ??? Does anyone know what these Black Strips are used for and where to buy replacements for them?
Thanks.
Harold

 

I just pulled the same trim on my '68 and found the black plastic inserts you're talking about...and have the same questions as you. Will be watching...

 

I also found it on my 69 Cutlass, was told it was there to help not dent the trim from the clips when installing.