It sound's like the sensor is shot Greg. Either that, or the electric
fan motor went bad.....
Ground the black wire (from the fan harness) to a good ground, then
place the red wire (from the fan harness) on the positive terminal of
the battery..... did the fan go on?
If not, it's the sensor (I forget where their placed on the 2.8's....
either on the side of one of the heads, or the intake).
(It might even be that the harness leading to the coolant sensor, for
the fan relay, is simply not hooked up... you never know with these
older cars, as the wiring is usually all over the place for the 2nd and
3rd owners). :)))