Bought a couple more things for the project....
I picked up a brand-spankin' new ARB compressor from Craigslist and a seat heater kit from Amazon. The heater kit was around $63 shipped and includes everything to do both front seats.
These kits may be interesting for a heated bed setup........it appears that most all of the kits on Amazon use the same pads...they seem to be well made with carbon fiber tracks for the resistive elements.
The seat heater kits come with several options for the controls...simple three position rocker switches (off-low-high) and nifty little roller controls with 5 settings. These are available two ways....a dual-gang control that has both controls in one place and separate controls for each seat. I went with separate controls since there is no convenient center dash location for the double control unit.
The heater pads were quite easy to install, I just unhooked the factory seat covers where the back and bottom of the seat meet and slid them in. I've been curious how the seat covers conform to the concave surfaces of the seat....they do it with crazy thick velcro strips. I didn't have to remove the covers to get the pads in.
I fabricated a small plate to mount the passenger control; if the heaters work well I'll probably relocate the control to the dash plastic. I need to extend the wiring for the passenger side since that seat swivels; the drivers side should be fine.
not done yet....