Deve,
In my case I wanted less clutter in the engine bay, so I mounted ALL of my electric controllers/relays under the dash on the firewall (Fuse Panel, Headlight Controller, Fan Controller and Power Antenna Relay).
As for two sensors...I only want/need one because I only have one fan. Are you think of putting two sensors in one lug to help eliminate clutter?
The bypass/override switch woud be a good idea as lomg as it's in the 40 amp circuit so the controller could be completely turned off in the event of a failure.
Mike B
