Most early Z's had clear glass but testing parts show defrost wires.

 

20 minutes ago, 240260280 said:

Most early Z's had clear glass but testing parts show defrost wires.

Deluxe models (Fairlady Z-L and Fairlady Z432) had rear defrosters from the beginning of production.

 

Gentle explanation required, evidently.  The Nissan / Datsun model S30 was offered in several different platforms as you know.  The platform initially exported to North America was not equipped with rear window defrosters amongst other items that were standard with other platforms destined for other markets.  This is one of my reasons to deny the idea that the "240Z was made for America".  The 'test' cars were so equipped indicating that the car was designed and produced at the time but this isn't what we got.