1986 454 TBI swap

[BigBlocksRule]

I have an '86 2WD 1-ton dually, straight, with a 454 and TH400. I'm gathering parts for a TBI swap - I want the reliability of TBI plus I'm swapping in a 4L80E. I love the old square body duallies and need a shorter truck for work, currently use a CCLB '97 and it's a beyotch to get turned around with a trailer.
I already have the dual tanks with TBI pumps in 'em along with the valve and switch. I don't want to use GM's TBI intake, or the Edelbrock for that matter. I would rather use a low-rise true oval intake since heads are '96 L29 Vortecs. Engine has been rebuilt but I don't know the mileage, wires were eaten off by rabbits and I'm just getting around to working on it.
Question: I found a guy with a '92 harness/computer that should work, came off of a truck with 454/4L80E. If I go this route, where would I mount the computer? I can fab a watertight box for a fender, etc., but I'm curious about where you guys that have done the conversion have put 'em. Also, is an unmolested wiring harness and computer worth $150?

[Zane M]

I haven't done a swap, but if I were, I would put the computer behind the glovebox like the factory TBI square body trucks. That is, provided the harness length would allow that.

[wyattglock]

To answer your last question of is the unmolested harness and computer worth $150, absolutely! A good harness can run from $250-$500 aftermarket. The ecm usually runs in the $100 range from most parts stores.
Mounting behind the glove box will probably be your best option.