[Roadsters] KA24E tach wire?

[Paul Kort]

  Dug my roadster out of winter hiding about 6 weeks ago and found the
parking lights didn't work.  Went through all the normal checks, and still
no lights.  So I took off for the race barn to get some help.  15 man hours
later I still had no parking lights AND only 2 brake lights!  Long story
short, we have now pulled the PO's wiring nightmare out and replaced it
with a 1969 2000 harness.  Found two switches that didn't work right so we
replaced them while we had the car apart.
  5 weeks later, everything works, except the electronic after-market
tach.  Some where in all the notes we made, we've lost what ever wire
coming out of the KA's ECU that makes the tach something more than a dash
ornament!  The KA and ECU are out of a 1989 240SX.

  Any KA owners out there that can lead me to the right wire?

Paul
Ohio