Since the original motor was computer controlled, we removed the original computer and mounted the “new” 1990 S-10 computer in the same location under the dash behind the radio. We also hung the electronic spark control, fuel pump relay, two fuses for the electronics, etc. off the computer bracket. All the wiring shown in this photo is part of the new Painless wiring harness. NOTE: you can see the radio in the left side of the photo.

Additional note:  The above worked fine in the summer when I used some shut off valves in the heater lines under the hood to keep heat out of the passenger compartment. However, when I turned heat on in the fall, intermittant engine and computer problems started showing up. The above picture is probably not the ideal location for mounting the computer since it is near the heater core and one 1990 GM manual warns against getting the computer hotter than 185 degrees. I've since removed the brace between the computer and the heater core case and turned the computer 180 degrees, moving it about 6 inches further to the driver's side. So far all the flakey computer problems seem to have disappeared. Unfortunately, that location wasn't real good either because now the wiper bell arms ran into the computer case.

I ended up fabricating a new bracket that wrapped around the original bracket, used the original cowl bolts, and shifted the computer about 4 inches further down from the top of the dash and three inches further back away from the firewall. It now sits above the stereo and is actually a more accessible location than before. Here is the computer in its' final location. The ESC, relays, fuses, etc. are now under the stereo and above the A/C.

Here's a shot of the new bracket wrapped around and attached to the original 81 computer bracket.

Next step was connecting the new electric fuel pump to supply 13 PSI of gas. I made a bracket for the pump that attaches to one of the gas tank mounting bolts so the pump would be below the level of the gas tank shown in the background. Note: there is a metal rock shield I made to protect it but that is removed so I could take the photo.

Note: this really isn't the proper fuel pump for a TBI and is probably going to be replaced soon. Update 4/2/07 - I replaced the above fuel pump with a Holley 12-927 specifically designed for use in TBI applications. It fit in place of the above unit, is "pulse less", and MUCH quieter than the above unit. Looks a lot neater also ...

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