[Vwdiesel] oil pressure sensore.

[cass]

hi..
found homes for all wires that are original
(ok..alot of thinking for them three wires!!!)))..in this 81 na 1.6 jetta.
have two wires that are from p/o's instal of 
jetta gauges.(oil pressure..temp(says coolant but could be oil?)
and alt.
question.,,,,,,,
on the side of the head Where the oil pressure sensor usually is, 
is  
a fitting with two things plumbed  into it on a tee...
one..a SMALL sensor..possibly a temp sensor??(says parts place)
and
what looks like an after market oil pressure sensor(looks like a tiny little canister.)
i checked at my parts store..and the oil pressure sensors they have are smaller /different letters beside terminals..
this one has two terminals.. 
one says 'WL/G'
second says 'S'
anyone familiar with this set up?
hints to how or where to hook up the two p/o ,s wires?
i know from parts store that the oil pressure sensors they sell..one terminal is for
gauge..and one is for old /oil blue wire for dash.
not sure if this is the case on this one as i dont know what the letters stand for?

anyone?

thankyou...ONCE AGAIN!!!   :o)