Ok, so, now that we know what's going on, here's how to gain access to it...
Remove clock bezel and bezel below clock
Remove rheostat knob and headlamp switch knob (you might have to use a slotted screwdriver inserted between the bezel and the knobs to pop them loose)
Remove headlamp switch bezel
Remove the four screws holding the cluster in place
Remove the two screws holding the top of the steering column trim in place and lift trim out - set on top of dash and leave screws in their holes, so you'll find them
Next, remove the three plastic clips that hold the front edge of the dash insulation piece in place and, also, remove the rubber donut around the floor vent
Drop insulation panel
Crawl under dash and reach up behind the speedometer, turn collar on speedometer cable counter-clockwise until it disengages the speedometer
Crawl out from under the dash, then pull cluster toward you and up onto the steering wheel trim piece
Remove the tach wire, clock wiring harness, the round plug, the half-moon plug, and, if your car has either cruise and/or an autotragic, remove the wires for the speed sensor and/or the overdrive wire from their terminals - If you do have working cruise, make note of which terminal the blue and gray wires attach to, so you don't get them backward and fry the speed sensor when you reattach it
Now, remove the cluster
Place it on a flat surface and remove the four screws that hold the tachometer to the circuit board
Use a slotted screwdriver to pop the tachometer out
Next, do what I mentioned in my previous post.
Reassemble cluster, and reinstall it. Fire up the car and take it for a test drive to see if everything works normally.
-J