Electronic Ig Control Box on a 85 D100 Off Topic

Not sure about the lean burn but yes it should have an ignition box. on my 85 2500 Ram it was on the firewall around the master cylinder. You can trace the wires from the distributor to it or look for the 3.5" x 5" box, should have a wire harness with 4 or 5 wires pluged into it. I don't have a pic but that should get you close.