Fuse is 8 amp. No signs of modifications. Both wires on fused side of no. 4 fuse block enter a large bundle of wires. The cover was examined closely to find the answer to my question. Note the imprint OXS in a different font and all caps. A late addition to the cover, probably just for the SC and later. Could not find it on any wiring flow diagram.
Thanks for your input! I later checked the fused side to the oxygen sensor. That wire is connected to the sensor. Answered. make sure to have your ex