I did the oil pressure gauge install and wrote up a few words on it.
It's on vanagon.com, but also on my VW webpage (see .sig file) and
click on the oil pressure link.

If memory serves, S goes to the gauge, WK goes to the idiot light
("W" presumable meaning "warning").

-Karl

Karl F. Bloss - blosskf@ttown.apci.com or bloss@enter.net
Trexlertown, PA
'87 Vanagon GL Weekender "Beverley"
http://www.enter.net/~bloss/vw/