How rare is electric rear defrost?

Thanks. I didnt see those when I posted.
Any pics of the firewall hole location?
Looks like you got most of it.
The white conector with clips probably went to the fusible link which is connected to the starter relay.
The other connector to the alternator output wire. if its there, might want to include it in the package.
I assume the standard output wire was eliminated, although it wouldn't matter if it wasn't.

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Here is a pic of the firewall. See that yellow splotch of paint? Right by it is the hole that that harness with the 2 white plugs came thru

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