[DavidG]

Chris,

It would seem that the windshield glass has already been replaced at least once over the ensuing ninety years as that marking is for an aftermarket glass supplier, not one of the original suppliers of safety glass to Ford (in addition to its own production of glass).

As for the effect on the value of the truck, having safety glass all around would seem to me to be a plus, not a minus. If you are unsure, ask your local glass supplier to furnish your new safety glass without any trademarks and add Ford trademarks at your convenience as all-around laminated safety glass was a extra cost option when your truck was new.