Yes, the original Goodyear Polyglas tires just said "Polyglas" on the sidewall, not Polyglas GT.
I am just looking for the actual Pontiac bulletin that Pontiac would have sent their dealers notifying them that the Goodyear Polyglas tires were now available for the 68 Firebird 400, and that they were white-lettered, not white-striped.
BTW, here's a 1968 ad for Goodyear Polyglas snow tires.
I'm not saying that the white letters were NOT offered, I just wanted to see proof. The author of the statement that Goodyear Polyglas tires became available mid-year 68 must have that document. If the author obtained that info from Gary Witzenberg's "Firebird" book, I'll take that as valid proof too.
