Progress today:
1. Bought the Platinum heat control film at HD -- like $30.
2. Got the window apart (it's a "test" window, one of the narrow ones). Small didn't mean it took less time. As a matter of fact, even though there were small bubbles in the film, it was stuck tight to the glass and in good shape. Getting it off was a trial compared to the previous two large windows. It seemed logical that a very strong wood scraper would work best, but in the end it turned out that a
single-edge razor blade was far more effective.
3. The weather striping comes off easy with a dull chisel. It's also easier to clean the residual glue off the frame if you do it before you take the window apart. You can see the rivets that need to be drilled out in an earlier post.
4.
Good News!
GOOF OFF (petroleum solvent based) and
GOO GONE (citrus based) are much better at removing residual butyl and glue than MEK. Much better. Did I say much better?
5. Once the frame is off, you have to strip away the foil tape and then gently pry the glass apart and dig the butyl out from between the panes. You'd think it would peel apart, but most of the circumference has to be dug out--just be careful not to stress the glass with an edge of the screwdriver.
6. The dimension of the inner glass is smaller than the outter glass by about 3/32 on the long edges and 5/32 on the short edges. When I did the trial with the new gasket (see earlier post), the gasket did not pull down tight to the frame on the inside and this dimensional difference is the reason. I think this can be helped by putting the butyl right at the edge of the outer window, which hopefully will make a nice filler for the gasket. It isn't easy to see, but this is the inner glass lying on top of the outer glass. It is interesting that the inner glass has more curvature (at least in this pair of panes), so the gap at either end is about 1/4". You can force the panes together with one hand at each end, but it doesn't feel comfortable. Ick. I hope this doesn't make taping the panes together difficult. I intend to use heat duct foil tape all the way around, slit lengthwise so the width is appropriate.
7. The film goes on easily. However, handling the film before it goes on is really a two-person job, if you want to avoid creases and dust on the surface. One person can do it if you build a small frame to help hold the film while you wet it and strip off the clear protective layer. I used the recommended attaching fluid, but I think water with a tiny bit of detergent would work. Once you squeegee it on, you need to trim the edge. I kept two of the existing edges just inside the edge of the glass so I'd only have to trim two sides. The trim line isn't critical (I think) because it will be under the butyl and hidden by the gasket.
8. The finished product is not as "platinum" as I expected and not as reflective as it appears in the photo. More than plain glass, but certainly not California Highway Patrol sunglasses! The tint of the film looks darker in the photo than to my eye.
9.
Bummer time--the directions says the glue "cures" in a week to 10 days. I tried to use a heat gun for a few minutes, thinking "warm and dry=cured."
NOPE! Put the butyl on about half way around and wound up pulling the film away from the edge. This stuff is pretty forgiving--peel it up, spray, and squeegee again and you're good to go. You can remove trapped crud if you need to. 
10.
Second Bummer--you can see in a photo of the trimmed edge, above, that I got a fair amount of dust under the film. And the film is slightly abraided just from rubbing around in the box, not to mention a couple of tiny crinkles while I was cutting and fitting it. But I think this will be good enough if the film sticks down tight in a few days.
More after the glue cures...
Zep