Posted for "Colyn Case on earthlink" <colyncase@earthlink.net>:

I used something called goof off to get it off my primed fuselage. I don't
know if it's safe on windows.

Colyn
 

[Thanks, Colyn, Goof-Off is already on my list.  I did manage to clean about 1 square foot in about an hour using carb cleaner... it softened the dried on glue nicely, but evaporated too quickly to moisten the dried on masking paper shards.  (This stuff has been on this airplane going on 2 years!)  BTW, I did test it in an out of the way corner and found that it had no deleterious effect on the window... what a relief.  Carb cleaner contains acetone, toluene, MEK and propane.... since there are no chlorinated solvents, though, the plexi appears to be impervious to it.  Needless to say, I was pleasantly surprised and relieved. Anyway, I'll probably follow another of the suggestions and use something like naphtha, jet-a, or kerosene on a damp rag held against the window under some plastic to keep it moist.  Hopefully one of those liquids will not only soften the paper but the glue as well.  What a nightmare. 

   <Marv>  ]