that don't make since "65 c10 350 soon 283 tbi 700r4 ps pb"

you got a 350 in a nice project, but you want a 283 and put a TBI system that would be designed for a 350?? I don't get it. run a carb or put the TBI on the 350, yes the TBI manifold will work on the 283 but it don't make sinse to use it, you probably want gas mialage with the truck, but you ain't gonna get it with a '65 2.5 ton ( approx ) Brick wall, the smaller engine might even make it worse as it runs harder to move the truck than the 350 would, a TBI 350 might be decent for the vehicle but by decent I mean 10-14 MPG, round that with the 283 with your mismatch setup. your power steering ain't gonna help the situation as it takes power to run it. your 15, you are going to want somthing simple, get a 4bbl manifold and carb of your choice and hook it up to 1 of the motors, you would have no computer to worry about tuning and programming.