Remove the padded dash as outlined Here. It is also helpful to remove the steering wheel with a puller but it isn't necessary. It just gets the steering wheel out of your way and makes it easier to remove the plastic cover from around the steering column.
1. Remove two phillips screws retaining the lower plastic steering column cover plate and remove the cover plate.
2. Reach up from the floorboards and behind the instrument cluster and carefully remove the speedometer cable. Just squeeze the round plastic clip at the flat part you feel and gently pull the cable away from the speedometer.
3. Remove the plastic cover from around the steering column. These are often attached with a long metal clip holding the lower part together at the bottom rear or toward the instrument cluster. These clips are often missing but if it is there then take a small thin screwdriver, slip it up into the split at the rear, and work the clip free.
4. Now take a shop rag or something similar and lay it over the top of the steering column to cover the ignition switch mounted on the top of the column.This will protect the cluster as you pull it toward you.
5. The cluster is attached with four 1/4 inch hex screws, two at the top and two on the sides. Remove these screws and carefully pull the cluster free from the metal dash enough to get your hand behind the cluster on the right side. Locate the long connector plugged into the cluster on the right and toward the center and find the top and bottom ends. Squeeze these ends at the same time and the connector will pull free. Try to do it gently if this is an original cluster. There is a printed circuit board on the back of the cluster and the brass ends can become fragile over time.
6. At this point, if you have a tachometer equipped cluster, you need to disconnect the black connector with the red and black wires. The wiring harnesses for cars with and without tachometers are different. This includes the wiring going out to the engine, alternator, and gauge sending units. The clusters are disassembled similarly however. Otherwise you are ready to completely remove the cluster. Move the cluster toward you and up a bit to clear the steering column and then move it to the right and away from the dash.
Gauges and Lenses
Place the instrument cluster face down on a soft flat surface and observe the back. You see the printed circuit board, illumination lights, connector plug opening, and the gauge nuts. The gauges are attached by round brass nuts holding them to the case and making contact with the circuit board. Keep in mind that the gauges are held in place centered in the openings where the contacts do not touch the metal case. This is important because if the gauges are installed incorrectly and touch the metal case, they will not work. Also notice the 1/4 inch hex screws that hold the case together. The plastic protrusions they screw into are very fragile. When you remove or install these screws, it is helpful to hold the protrusions with your fingers to keep them from twisting. They have been known to twist and break.
To disassemble the cluster:
1. Remove all illumination lights. These are small 194 bulbs in black plastic cups that twist slightly counter-clockwise to remove.
2. Remove the brass hex screw on the circuit board shown at the upper right in the picture.
3. At the center is a rectangular component screwed to the back and connected to the circuit board by two snap in contacts similar to a 9v battery. This is the instrument voltage regulator. It sends a pulsating signal to the gauges in order for them to function. Carefully unsnap these contacts and unscrew the voltage regulator from the back.
4. Remove the brass nuts on the gauges and gently remove the circuit board sections from the back. On each gauge, there should be a small piece of cardboard where the threaded contacts of the gauges poke through. This cardboard piece is intended to hold the gauges in place and not let them fall out of the back. Remember to not damage or lose these pieces.
5. Carefully remove the hex screws holding the case together and the screws retaining the gauges on the sides.
6. The outer gauges remove individually and then the center section holding the speedometer and the other guages or tach.
Note: If you look at the outer gauges, you will see how a small hollow piece with foam attached is used to shield light from the turn signal indicators. Be aware to make sure these are in place when you reassemble the cluster so you won't have a turn signal arrow barely glowing at night with the lights when you're driving.
With the gauges removed, you see how the lenses install on the cluster. Now is a good time to wipe off any dust from the sections and the lenses. This is also a good time to replace those lenses. New ones can be purchased from many vendors. With new lenses, the assembled cluster will look like the gauges don't have any lenses at all, just like new.
REMINDER: If at this point, your intention is to remove or replace any gauges, remember that when they are in place, they must be centered in their mounting so that they do not touch the metal case. If they touch the case, your gauge will ground out causing a short or cause the gauge to read full very quickly which is hard on the gauge.
Reassembly of the cluster is obvious at this point. Just take your time, do it in steps, and then reinstall.
The printed circuit boards of these clusters should be replaced with new ones. This is highly recommended if possible. Over time, these get fragile but mainly the two plastic sheets that hold the runners can separate. This leaves open the possibility of accidental shorts or runner breakage. "In the old days," jumper wires were just soldered across breaks to complete the circuit. Also the runners at the harness connector can become loose and move out of alignment causing mysterious bad connections. A new circuit board will eliminate this problem.