I've had my carputer installed for over six months but just yesterday finally got a DC-DC solution working. I'm using the ITPS now and have removed my inverter. Here are the pics:
my Ford Ranger truck. I purchased this truck on eBay last year for $2900
Casetronic 2699R running behind the passenger seat (yeah, it's a little messy). The ITPS is in the little black project box beside the computer. I'm just using it for power right now, I don't use the shutdown controller yet.
Xenarc 700V is installed behind the airbag cover. There never was an airbag in the passenger side because it was optional for this year-model.
Here is the screen visible with the cover removed.
Next on the list to do: GPS