Oil temp gauge

[Marco Weibel]

Hello listers

1984 CGT
I am in the process of cleaning up the wiring behind the centre console...
As usual on a 30 year old car its not all stock back there anymore.
My question is particularly about the oil temp gauge wiring. 
What i so far figured and works:
There are two black round connectors that correspond  with the gauges. One bigger 4-pole connector brings 12V/ground tho all the gauge-illumination and Volt-meter and after about a foot long wire loom also has a white rectangular connector (double 6mm/double 3mm female spade) that i think once fed the OEM radio, right ? Thats all good.

Now there is also the small round 2-pole connector. 
I only have the gauge side of it. One of the PO must of tinkered with that... the car side is missing.
I only have a blue/white-ring wire (oil-preasure, right ?) with a self-crimped spade that was butchered on to the small round connectors blue/white striped wire. That works too...
What i am missing is the other wire that would work the Oil-temp which is green/black on the gauge side of the connector.

What color am i looking for on the car side ?

Is oil-pr and -temp coming in through the same loom ?

I even cut back the flex sleeve as much as i could to check if that wire was cut short and slid back into it but ....nothing.
Under the hood I checked continuity from the oil-pump to where the wire (black) disappears behind the firewall.
It's good.

Can i lay a new wire from the pump mounted sender directly to the gauge ?
Or is there something in between still ?

Thanks for looking

 Marco Weibel