Notso replied:

They are mostly at the back end of the gearbox and take a signal from the output shaft.

cloughie replied:

Do you mean the speed alarm that comes on at 105 kph or something to do with the speedo? If you mean the speed alarm and how to stop it let me know and i can help.

kev.h replied:

She sensor unit is high on right side at rear of gearbox (at least in auto) if you only need the sense wire for cruise control etc its the blue and white one coming into the dash panel on the left lower corner with a bundle of other wires
If its your speedo not working does the trip meter still work as they both use the same sensor easier than climbing under the car
P.S. Mine is a 95 assume its the same
cheers Kev