For a DD, you can't go wrong with an EFI set up. I have had it in mine for about 4 years and love it. I haven't had any major malfunctions so to speak yet, but the minor ones I have had were caused by the old parts (fuel pump & corrosion on spliced wires) going out. The mpg will go up slightly, maybe about 2-7 mpg, so there is an advantage there. The major drawback is that everything now relies on that electrical system to run. If you aren't versed in the workings and going ons of an EFI system, I would definatly recommend getting the owners manual and/or a Chilton's or Haynes manual for the particular donor vehicle. As to what system to use, the car or truck, use the car EFI. The truck plenum is taller than the car by several inches and won't fit under a stock hood and stock height body. You have to have a minimum of 2" body lift and an aftermarket hi-rise hood. They are just real tall whereas the car EFI is low profile. Mine is a car system and fits under a stock hood with no body lift. Also what ever you get the system out of, try and get everything (fuel rails, pump, intake, heads, plenum, wiring harness, EEC, etc.). EFIs from (if I remember right) 89 on had the mass air set up where most other pre 89 cars had the speed density system. An easy way to tell is that the MA had 19lb injectors which were orange and the SD system had 14 lb injectors which were grey. But any way you look at it, for a daily driver or for a trail rig, you can't go wrong with an EFI set up. I will try and take a picture of my set up tomorrow and post it up for you to look at, but definatly, I highly recommend going in that direction. Any other EB that I build, unless I get a complete cherry, stock EB, I will put EFI on it, no doubt about it!