I dont exactly know how to confront this situation. it was just patched with angled sheetmetal that was epoxyed on. but it still leaked. I want to get it right while im doing the resto. THere is very little rust anywhere on the car but this rear window channel!

here are some pics (the sides of the window channel are very solid)

http://www.garsworld.com/rust1.jpg

http://www.garsworld.com/rust2.jpg

http://www.garsworld.com/roofrust.jpg

You can buy that lower panel and weld it in. I just did mine.
Want to see somthing scarey lay in the trunk on your back with a drop light in hand then look up under that panel. hehehe, sorry I just remember my jaw dropping.
For the other stuff I brazed in some metal I wanted the brass in there.
But stay away from the lead in the quarter panel at the top left and right corners.

The rear window to trunk filler panel will cover that rot on the lower windshield but first I had to fab something to weld it to - no replacements for the lower panel available for the 66. I had the same issue on my lower section, though it was more on the driver side and not on the passenger side. Since this lower panel is hidden, I fabbed up some sheetmetal that closely resembled the driver side (only reversed) and welded it in before I fit the rear window to trunk filler panel in place.

I also had some of the upper window rust, though you have more (aren't you lucky?) Best thing to do is cut out the rot, fit then weld a strip of sheetmetal back in there. You'll probably loose the window molding rivets in the process but you can buy screw-in post replacements at Mr. G's site or if you have a stud welder with the proper attachment and studs, you can replace the studs with that.

If you have any questions, feel free to PM me.

Stud welders are awesome inventions, but should be priced more according to the frequency in which they are used. I know mine was like 300 bucks, and I've used it two times. although I still need to weld in the molding rivets, and then it will have paid for itself. JN

Just buy some stainless screws the right size and dip them in paint or something to seal the screw hole and screw in the clip.
That has to be done before the glass is put back.
Besides thats the way they did it at the factory on some models and no one is going to pop out your molding to see it.
I would suggest a 110volt small mig welder if you don't have one it'll come in real handy when you start fabricating all that repair metal.

i have a wirefeed welder that i rarely use. the body shop quoted my about $240 to fix the rear window channel. I think i will give it a shot and hopefully save the money. I have some angled metal that fits perfectly but its kind of thick. Im afraid the it will affect the location of the studs (meaning, they will be moved that much closer to the window and the molding wont fit right especiall)

$240.00 sounds real cheap to fix that correctly.
A body shop might plaster all that up anyway they can to get some paint on it only to have it not last more than 2 years if your lucky, By then the rust will have taken an even bigger toll.
Better to kill all of it now and get it over with.
Why did the factory not paint any backsides of anything?

It is almost an art to welding sheetmetal without distorting it just weld small amounts and let it cool.

small trick I learned for welding sheet metal is to take two rags and soake them in cold water and place them on eather side of the welding area and keep soaking the rags as you move along. this should stop the steel from over heating, but take your time.