SARD oil pressure gauge - help

[XJS]

Bought as used on ebay a while ago. I've got the gauge itself, the sensor and the harness for the sensor, but no manual and main harness. Wrote emails for all known SARD distributor asking for user or installation manual to BUY, got only one response, describing their business policy not to support secondhand products. So, I'm after any suggestion for wiring this unit... It has a 3 point connector for the sensor harness, and a 6 point connector for the main harness. We're able to recognise three out of these 6, ground, switched 12V and lights, so the gauge is working, but not fully functional. The additional 3 point is for the constant 12V for the memory function and two output, one for the datalogger (sensor output) and an other for the warning output. Unfortunately without these pins the unit are not functioning correctly, for example the warning LED are on, and can't be switched off..a little bit annoying.
So, to keep the long story short, if somebody has any idea or manual or how to wire, or knows somebody who using it with success, it will be really appreciated.