is fitting heated mirrors really as simple as upgrading the glass to heated glass?

i hear that the wiring runs all the way to the door.
and that the heated mirrors come on when you put rear window defrost on.

so is it really as simple as just upgrading the glass?
has anyone done this?

also has anyone used wide angle glass replacement mirrors like these?
they look slightly larger not having the plastic surround on the mirror glass which i like and also if they are truly wide angle they may very well negate the desire for the little round blind spot mirrors i have.

https://www.ebay.com.au/itm/14251518...EAAOSwcPhllrOD

 

You can look at the mirror connecter and see if the wires are there on the mirror side before digging into the mirror and may be able to read if it is getting heat power once commanded

The mirrors have like a 6 inch pigtail but the interior door panels have to be removed , but I can be wrong

I changed my mirrors to chrome which is after removing the whole thing just a shell that prys off with some special tricks without removing the whole assembly from the car

 

i will check when i get the chance.
gotta take my mirrors off to check out the up down motor on passengers one anyway at some point.

was just thinking someone might know already.