Eric: Perhaps your windshield frame was replaced at one point? Or perhaps yours was just glued on rather than rivetted? I think the ones around here were just glued but would have to check the pile of windshields out at the scrapyard. They were very very judicious in making sure all the M151A2 fleet was done. I remember them being sent away when I was militia. When I went regular force and was on my TQ3 training in Borden (1981) they even sent in the training aids for re-application of ziebart. It made a real mess of the hands and the crappy swarfega mechanics soap we were issued back then was no match for the ziebart. A dip in the solvent bath would make short work of the ziebart mind you.
The dirty hands.....23 years in the 411 trade and you kind of got used to that.
I think I am starting to ramble a little bit.