Neil,
Right on. You are clearly reducing your total footprint with most of the mods you've done to your car. Is there anyone out there getting better than 46 mpg in a scion!? Fantastic dedication.
Per your question on how many gallons of fuel you've saved in terms of the plant and animal mass required to make that fuel: It prompted me to visit the wiki page on fossil fuels:
Fossil fuel - Wikipedia, the free encyclopedia
Truly alarming to see the estimate of 23.5 metric tons of organic material to make ONE liter of gasoline today. Too bad they don't have American friendly units, as thats nearly 100 tons per gallon. Yikes. Just another reason why anyone who thinks that there's no reason to conserve energy is completely insane.
Anyway, my point was, that if you found out the total amount of fossil fuels consumed to make that set of monitors and cameras, you might be quite alarmed also. Feeding, heating, and transporting the employees, powering the office space to design it, transporting the raw materials to make it (including fossil fuels to make the plastic), then packaging and shipping it to your door, well, doubt you'll ever save that much fuel from using them. But that is a major buzzkill in your pasta. And who knows, you are the best candidate for extracting major gains out of something like this.
So the cameras have night vision, but how does that interface with the monitors? Is there a switch to activate that mode on the camera? What type of cable interface does it require?
Are you mounting them on the Sail panels of the doors? Or inside the a pillars on/in the dashboard?