Z28 Cluster Instalation
After many years of being on the fence, trying to decide if I wanted to go with the Z28 cluster, I decided to go for it.
Gary Meier "LS1 MM6" gmparts@nycap.rr.com who is well known on http://www.impalassforum.com/ builds the units, and through years of endless effort has come up with a great product and has the patience to help those installing it by answering questions I'm sure he has answered a thousand times. He also builds cruise control units and pass to flash for our cars.
I've never seen a detailed write up on the instalation, so I brought out the camera and tried to hit the highlights of the instalation to help those who decide to instal it in the future.
Here is the Caprice digital dash. It works fine, but lacking a sporty appearance and does not have a tachometer.
Start by removing the bezel around the old cluster. Remove two screws under the top edge and the bezel pulls straight out
Now remove the screws that hold on the lower dash panel. Hidden screws are, one inside the side fuse panel and another hidden by the cluster bezel. All others are under the dash. Once all screws are out, the lower dash panel pulls straight out. Resistance will be felt from the retaining clips. Make sure you keep the glove box open for removing the lower dash panel
Now it's time to remove the dash pad. Side plastic window trims pull straight out. They are held on with tension clips. Then remove the defroster grill by prying up on the rear edge with a thin screwdriver. Once up you can twist out the headlight sensor. Then remove the vent trim on the passenger side. It also has spring clips holding it in place. Along the rear edge of the dash pad remove all screws holding the pad to the dash frame. Now pull the dash pad straight out.
Now you have plenty of working room which really makes the job easy
Now that you have everything out of the way, remove the four screws holding the old digital cluster in and pull the cluster straight out. Now start removing plastic from each end of the dash. You cans see how much I removed, but you can normally get by with less removal than I did. I used a drummal tool with a steel bit used for cutting plastic. The bit was less than $3 at Walmart and well worth it. You can also use things like a hacksaw blade to remove the plastic.
Here is the new Z28 cluster. You'll see the two wire harness connectors that plug into the dash and one wire that runs for the tachometer. Using some universal banding I made brackets that run from the cluster to the two lower screw holes on the dash. This helps keep the cluster in position.
Running the wire for the tachometer is very easy. Gary supplied a length of wire with the pin that needs to go into the PCM harness. Run the wire through the firewall and to the Red PCM connection. Pry open the connection tabs and find the empty slot labeled A13. The pin on the wire will push straight in. Close the plastic cover and plug the Red harness back into the PCM.
While the dash pad is off, it is a great time to remove the resistor for the oil gauge mod that will allow you to have an accuate oil preasure gauge. Remove the glove box and locate the small gray plastic hold downs just above the glove box. These hold the harness where the resistor is located. Remove the hold downs and pull the harness down to gain access. Remove the sticky tape and locate the resistor. Once found snip off the resistor, tape the end and put the harness back.
Now replace the oil preasure sending unit with one from a 9C1 Police car. The 9C1 sender is a 0-80 lb sender that will work perfectly with the Z28 80 lb oil gauge. You can see the difference in length but the wiring connection is the same. GM part number is 10201491. NAPA part # OP6676. I and many, have opted for the 0-60 lb sending unit from a GM truck to make reading the gauge easier. The part number is GM 12553175. To instal the 0-60 lb gauge you need a 1/4 inch female to 1/8 male pipe thread adapter, which can be bought at most auto parts or hardware stores for about $1
Now comes the part where you keep moving the cluster around to get the best fit. Attach the cluster to the dash with the two screws. Set the lower dash panel on and using the cluster bezel, I kept fitting the position of the cluster. This is not hard to do but it is time consuming. In this photo I tried to fill the gap with foam tape, but found if I took my time I was able to have a very close fit without it.
The black foam tape worked very well to fill the gap around the steering column. From the factory is a rubber surrond, but mine had gone bad many years ago.
Finally I reinstalled the dash pad, lower dash panel, glove box and all the trim. Here are some pictures of the final instalation
I hope this helps those of you who had questions about the instal of the Z28 cluster. Gary makes a great product and the instal is not hard but a little patience will help