wiring gen3 duster

What type of computer? If it is a small one like FAST uses, it can probably go behind the glove box, if it is a larger one like the Holley HP you are going to have to be creative depending on what you want (see it or not). I have a Holley unit in my 70 Challenger and it is mounted above the inner fender brace inside the drivers side fender. Its water proof so it can live there. On my Cuda I mounted it behind my glove box (FAST unit).