99% it's UV curing toughened cyanoacrylate.
A windshield is regular laminated glass.
Have you considered marking the spot from the outside with Sharpie or grease pencil, then scuffing the inside with fine wet-or-dry and cleaning with drygas (pure isopropyl alcohol) ?
It's hard to get a cleaner surface that one freshly abraded.
Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.