I see what you're saying about the light...especially considering how the side mirror circuit is configured. However, I don't think the light will be an issue. Both relays are exactly the same part, so ostensibly they will deactivate at the same time.

My plan is simply to splice and feed the red/yellow wire that activates the rear defog relay to the blue/yellow wire that activates the mirror defog biz-ness, snip the excess, and take away the un-needed switch/wires. The power that feeds through the switch is just a momentary event that pops on the relays. The actual warming of the glass occurs via separate circuits.

I guess I should just try it and see if I a blow a fuse. No harm, no foul...maybe? THe other option is to just get rid of the mirror defogger. It doesn't make much of a difference as far as I can tell. Perhaps if the weather were more Portland-like... Alas, along with the seat heaters, it may be a bit of a wasted amenity down here in Texas.

Thanks for the response, as usual.

WW