That is call a drive by wire throttle body which you need the gas pedal for it work.
Thanks, I hope it helps you out. I just put up my costs so that might help too.BTW, I just finished your build thread. I liked it. definitely going to be referencing it even though your's is 6.0 and mine is 5.3. The harness is the most intimidating part of it. And flashing the computer. Not even sure how to go about that one. Oh well, I'll get there.

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Your steering box will have to be replaced by an 1981 box or newer, it's simply the same box with a different style fitting that is still used today and the LS power steering pump lines will bolt in to the 80's steering box.