I have a Defroster in my '72 GTO. It is an extremely rare option here in Az. The defroster/defogger switches in the GTOs are different from each other. The defroster switch has a light in it, the defogger switch does not. I think the light is an amber color. The GPs from the same years used a different back glass but they did use the same switch and it is much more common to find a GP with this option than a GTO. Keep an eye out for a defroster switch from a GP. Steve
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