I talked to Kelsey, they said Polyglas with no size on tire was correct for 69 SS. My spare is a Polyglas, but white stripe (04A). Is the Wide Tread and not the polyglas the correct tire for 69 SS for raised white letters? What about optional tires like PL5 (standard on SS?), PY4 (white stripe, fiberglass belt=Polyglass?). I need new tires and want raised letters but also want the correct tires.