> Yes it is still a stock 1.9L. I still have the original cluster. Could i
> swap the circuit board? 

Actually, the early model just uses a simple passive system: If the .3
sensor closes contact, the oil light comes on. The newer system runs
everything thru a small L-shaped circuit board inside the speedometer
housing. Probably the easiest way to keep the system from switching
focus from the .3 sensor to the non-existant .9 sensor is to cut the
trace carrying the tach signal to the board inside the speedometer.
The board is fed through a long multi-pin header along the top edge of
the rear of the speedometer.

>The 2.1L "2" switch setup, is this 2 senders? Can I
> replace my sender with the 2.1L sender?

Well, the 2.1 has two sensors: the classic sensor below the pushrod
tubes on the left side of the engine (.3 bar) and a additional sensor
below the water pump (.9 bar). Having only seen it in passing in the
Bentley and ETKA, I'm really not familiar enough with the 1.9 engine
to say whether one can add a .9 bar sensor anywhere. Perhaps someone
on the list with actual firsthand experience could shed some light on
the subject.