the back glass on my 74 is caulked in with something thats rock hard and has a very tenacious bond. this is something that someone has done, not factory sealant.
i need suggestions on the best way to remove it, its all around the trim clip studs and on the glass, and everything.there is no way on earth this window was gonna leak! lol.

My 73 Challenger was sort of the same way. It was black and oozed all over everything. It wasn't extremely hard though once you got past the outer crust. It was factory, on my car anyway. I know it wasn't the tape that people use to reinstall the glass.

I poked a hole through the caulking and inserted some braided metal wire through the hole. My dad and I sawed all the way around the glass.

Thin wire like guitar or piano, I use welding wire but it breaks easy, one person on each end and wire saw it right out, works every time for me. I usually also cut the outside with a razor knife first down to the pinchweld.

Most auto parts stores sell a specially braided brass wire for this job, can't/won't hurt the glass.

This stuff is white/ beige. Its over top of the original stuff. It's some serious stuff. I can't even mount my rear window trim bcse it's hopped up the clips, etc

Here's a link to the style windshield cut out tool that I use.
Windshield tool on ebay

The last one I removed had the sam black goop you refered to. I used a puddy knife and worked slowly around the window. Didn't take long.

so when i get it out, whats the best way to get that crap off of the glass? hte channel, thats a little easer, i can really scrape against it if i need to, but the glass....eesh! any suggestions?

bug and tar remover.

Long wire rope thin cable and a pair of gloves. Sometimes it takes 2 people though. If you think the glass is loose enough to "push it out" the rest of the way without cutting it loose first, you will break the glass.