The k car motor came in the beginning with the idiot light electric switch. They didn't use the hexagonal log that protrudes from the block (like you find with the GT option with the electric oil pressure sender). They made or had made a square extension fitting approximately 3/4" X 3/4" X 3" long. The square end of the extension is tapped for a series of odd ball fittings (running straight out the end) that eventually turn into a cloth braid covered high pressure tube that runs along the inside of the drivers side valve cover straight back through the firewall (to the gauge pod). What did they do with the wire for the idiot light? Good question. I have seen a couple of things done. Left hanging out of the way, cut off, folded back and covered with tape, and just plain I can't see it. One of the 1965 road tests done by a magazine says their test car had a gauge and the idiot light.. I have never seen a "real" car with a fitting that would do that. I have seen some that have been made by somebody like me. (a lousy faker artist) good luck! jimbo