Spotted it the other day when I was swapping out all my instrument cluster lights with LEDs. Its behind and above the instrument cluster toward the back, left side. Can't remember if you can access it just by removing the cover over the top of the cluster alone, or if you have to dig more into it. Plug was on the left side of the unit near the top of it.
If you need to dig deep into it here's the guide I followed
Gauge Cluster Removal , only on mine (1990 N/A) I had to remove the trim panel below the steering wheel to access the back 2 of 6 screws on the bottom of the steering wheel cover in order to remove it. I'd take the top cover off first and see if you can get at it without taking the whole thing apart
