I finally got around to popping the rattling, loose rear window out and found that the previous owner jammed just about everything he could find between the glass and the trim in hopes of quieting the rattling. This, instead of just repairing the window.
Here's a pic of about 1/3 of what I pulled out of there. It included corrugated cardboard, bits of styrofoam, wood shims, folded up matchbooks (with a match still inside), the tag from a pair of Calvin Klein Sport jeans, and what I think was a matchbook from Arthur Treacher's Fish & Chips.
Butyl tape going in tomorrow along with the glass. Good news is that all looked dry and solid behind the backpad.
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