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Ram-Mount.com sells mounts for most if not all vehicles. Oddly, this version that uses your seat bolts to be held in place isn't listed as being available from them. If you serf the web you can find this version for sale by an on line seller but it won't be Ram-Mount. It'll be an on line company that sells Ram-Mount products. I bought mine from Ram-Mount two years ago and it was listed in their on line catalog at that time. Try down loading their catalog. It might be listed there.
Step 1Get a mount that doesn't need any drilling.
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This model uses the seat bolts so there is no need to drill holes in your car floor in order to attach the mount base.
I do use a laptop charger "in" the car. It keeps the battery topped up.
This project looks like I threw it together but its actually been evolving. I took the photos and created the Instructable after 2 years of trial and error.
Good luck with whatever you try.
I've been thinking about mounting the display on the dash board in front of me. The map images would then be projected (or reflected) into the lower part of the windshield. That way you wouldn't have to take your eyes off the road. I haven't worked out how to reverse the image thats reflected backwards into the windshield though.
To get an idea how that could work simply put a paper map on your dashboard.
It works better on overcast days but still looks doable on sunny days.
Their are a lot of issues to work out. For example, not bright enough in the day, to bright at night and don't forget the reflected map will be backwards.
Most engine info is all ready on my dash so I would prefer a dedicated diagnostic meter. Its not as sexy looking as a Tach or Oil Pressure but its more useful.
Here are some links you might find interesting:
file:///Users/williambudde/Desktop/YouTube%20-%20Video%20captura%20OBDII%20Mazda%20Miata%20MX5%20NBII.webloc
file:///Users/williambudde/Desktop/YouTube%20-%20OBDII%20Scanner%20Working!.webloc
file:///Users/williambudde/Desktop/YouTube%20-%20DIY%20OBD-II%20Car%20Computer%20Interface%20with%20LCD%20and%20Microcontroller.webloc
As far as the diagnostic programs, I don't use any. I use the gauges on my dash. I supplied those links to show you what others have done. Go back too "You Tube" and drop those posters an eMail. I'm sure they can help you out.
Just found this: SATNAV-HGV
Poor guy, imagine explaining that!