My recently purchased mod IV has been setting for ten years and the one D window has cracked 2/3's the way around on one side right on the stitch line. I was planning on removing the "glass" right at the window outline and gluing in a new one slightly oversized with a three inch fabric edge re-enforcement. Would anyone have any left over fabric for such a job and any idea as to what would be a good adhesive? Contact adhesive maybe?