1990 240 gauge install using turbo wiring harness and tach

OK, I have a 1190 240 DL wagon in which I just installed a tachometer.
I bought both instrument clusters from a turbo 240, so I put the tach
where the clock was, and have the oil pressure gauge and the voltmeter
which are not installed yet, but connected together with the turbo
harness. The turbo harness makes it much easier, because I can tell
exactly which wires do what. blue/red is power, green is oil pressure,
brown is lights and black is ground.... right?

Does anybody know which terminals on the back of the tach go where? I
can at least ground the gauges and light them through those, and
connect the voltmeter to the Ignition Only wire on the stereo for
power.... There are three terminals in this shape;
_
| | basically an upside down U shape....

I am trying to find the little harness that would go to the small
clock, but something tells me I won't end up finding one, soooooooo, if
someone has one, all I need is for you to tell me what color wires go
where, and I can probably figure out the rest. For instance; the
horizontal terminal at the top goes to a brown wire, the vertical
terminal on the driver side goes to a blue/red wire, etc.

Or, if there are serious issues with my plan, someone let me know so's
I don't blow up my vehicle, mmmmK?

thanks

P.S. I have the sending unit for the oil pressure gauge and that should
be pretty easy, once I get the adapter, provided that I can ground and
light it off the tach.

 

There were three wires on that plug. the harness colors were red, green
and black. They correspond to the three pins coming off the circuit
board that the tach plugs into when you replace the clock. You'll have
to trace them from the board but one was power from the dimmer rheostat,
one is B+ and the other was a ground to the clock and clock
illumination.

Bob

 

The green one is for the bulb holder and the dash illumination, the red
wire is your + wire and the black is the ground. I asked someone on
ebay who was selling a tach/ small clock/ harness combo. By looking at
the picture they took of the harness, I found that the red goes on the
horizontal, the green on the passenger side vertical, and the ground to
the driver side vertical terminal. Obviously I don't want to wire the
voltmeter into the B+, or it will be on all the time, so I just have to
find an ignition wire, which should be pretty simple...

I hooked the voltmeter up to the B+ to test it, and it works, but I
could only get the light in the oil pressure gauge to turn on, not in
the voltmeter... Maybe it is because it's a turbo wiring harness, and
there is no third gauge, kinda like christmas lights? should I connect
the loose brown and black wires at the end to form a complete circuit?

At least I got a reading on the voltmeter and a light in the oil
pressure gauge. I guess it's a start.... I can't start the car because
the head is still at the machine shop, etc.

Thank you for your help!

loren