Hello John,
I have an '86 2.1 It may be a bit diffrent but these ideas might help.
>I am trying to install oil pressure and oil temp gauges on my 1984 1.9L

>1.  I cannot find any location to install the screw in temp
>    sensor that I bought.  Has anyone installed an oil temp sensor?
>    If so, where did you install the sensor.
   I used a tee fitting in the stock temperature sender location at the
thermostat housing.  I know people have said that this causes an inaccurate
reading, but I use it for relative readings, not exact readings.

>2.  The pressure sensor that I bought is quite large.  It doesn't seem
>    like it will fit in the small space between the push rod tubes on the
>    left head.  Is there an alternate location, or do I need to get
>    another sensor?  Is the resistance of these sensors universal, so I
>    can use any sensor?
   I choose to remote mount the sender next to the coolent tank, and run a
plastic hose from a tee fitting between the push rod tubes.  Be careful how
you run your tubing near a hot exhaust or allow it to rub on anything.
>3.  I would like to preserve the idiot light function in addition to my
>    new gauge.  Can I just use a brass t-fitting and screw both sensors
>    into the t and screw the t into the crankcase?
   I always try to preserve the idiot lights, some times they do server to
catch your attention.
>I hope somebody can help solve the frustrating problems!
Colin A Moran

If you can't dazzle them with brilliance,
baffle them with bull sh*t.

 '86 Syncro GL