I have this sender which runs the idiot light as well as the console oil pressure gauge. Can anyone tell me which connection is for which application and where this sender is situated on the engine (1983 1.6 Turbodiesel)

G - Gauge.
WK - Warning light.
Remember the warning light is a normally closed type so if you have the "Buzzer of doom" system with 2 oil pressure switches this sender wants to go in place of the normally closed switch.
Easiest way to tell is the one with the blue wire is the normal one, the other one with the yellow wire is for the "buzzer of doom"