I have a 1967 firebird. There is a decent amount of rust on the rear window, at the top where it meets the roof.
I have replaced the rear window trunk panel, but is there a patch panel for the top of the rear window?

Any suggestions on fixing this area?

I think the top rear window channel is part of the roof. I may be wrong, and I hope I am, but I've never seen that offered separately. Is the glass out? How bad is it? Just some rusty spots or disintegrated? I had a '77 Firebird and it was just very rusty with an occasional hole. Some of the reveal molding retainer studs rusted out. I used a wire brush on an angle grinder to clean out all the rusty metal. The few holes I filled with an acetylene torch and a VERY small nozzle, like a #1. Then I rustproofed the whole channel with some excellent marine waterproof primer, then paint. Check with an auto body shop supply place. Sometimes they have patch sections for problem areas like that which no one else carries.