Heated Moto Mirrors

Sure can. Should be fine. They dont draw a lot and the factory wiring on those older kws is decent sized.

 

I just today installed a set of heated, motor mirrors (motor both sides) on my 98 W900. Not sure how your mirrors are but on my new kit the wiring is sealed from the bottom of the mirror in a jacketed cable.
It was pretty straightforward, was able to wire the heated mirror circuit to my factory KW switch, and had some spare switch holes for the two MotorMirror switches to go.
They sure give you plenty of cable on the drivers side mirror, Had to shorten that side up to keep behind my dash somewhat tidy.

 

The kit I got had 2 toggle switches and no bracketry to go on the shifter. The previous motorized mirror's control was mounted there and it was only a single side, maybe they don't have room for when both sides are motorized.

Not too worried, I didn't really care too much for the shifter mount, and having both sides motorized is the cat's meow.