Major Tom to ground control

"Ground" is the key word here. After final assembly of the oil filter / adapter, the oil temperature / warning light sensor had no ground. So, the oil pressure showed a constant 10 bar and the "idiot light" did not come on. An update in the ground connection was necessary - but how? The sender unit only has 2 contact prongs, one for pressure and one for warning light. The M10x1 thread for attachment to the oil line is conical, so, no way to attach a ground strap...
The solution was to ground the housing itself!
Today shown a little different - In a short photo story:

 (forgive my booger welds)

 a little zinc spray to avoid corrosion

 Ground strap attached! The sender is fully functional again