Heated/electric fold mirrors are on the JDM version of the Z, so it's conceivable the the wiring to complete the work is already in place.
heated mirrors
Heres a video of a setup
YouTube - ‪Nissan Fairlady Z34 370Z Automatic Sideview Mirrors Demo‬‏
Here's a thread on the 350z on making the mirrors electric.
The Nissan 350Z & 370Z Owners Club • View topic - Auto Fold Mirror - £35