masking vacuform canopies

Here's my solution,  I don't mask the VF canopies, I paint Tamiya tape, cut it into very thin strips and use the tape to make the glass frames. kind of "reverse masking "   then I simply future the whole canopy to seal and set the masking tape.  After the future i then painstakingly dull down the future on the tape frames.  does that make sense?

Hey Jay Jay, now that's a workable solution I can try. I will have to use the photos and the box art to

create the frames, glass etc, as this particular VF is virtually blank. Worse comes to worse, even if I have to 'square' the windows, it might work for me. There is a large area on the top that will be easier to mask. How do you 'dull' down the future? Thanks very much for your reply.