Monte Carlo: Custom Dash install

Tom McCoy

In this write-up I hope to explain the basic steps I took to replace the factory, poorly lit gauges
with much more adequate instruments. Before I go on, let me explain that I had installed water temp,
oil pressure, vacuum, and trans temp gauges in a Kirban Performance 4-gauge pod above the radio prior
to the project you're reading about.

First I bought the gauges I wanted. In my case they were Auto Meter Z-Series, 3.5" Speedo and
Tach, 2" volt and fuel gauges.. I removed the black trim in front of the steering wheel and took
measurements of the opening that the factory gauges were behind. I started with chipboard and began
making up template after template until I had a box-shaped piece that would hold my new gauges and
fit behind the black trim of my dash. This took a lot of time and measuring to get just right,
everything just fit..

With template in hand, I walked into S and P Sheet Metal (Toms River, NJ) and had them make
a custom dash plate that matched my template. They used a 1/8" thick sheet of aluminum to copy my
artwork. I painted the dash plate in trim black and mounted the gauges in their new home. The custom
dash plate with gauges installed was then screwed to the black trim with nice finishing screws I got from
J.C. Whitney. I had to remove the gauge carriage (plastic) and dermal the entire back side off it to allow
room for the extra depth of the aftermarket gauges and custom dash plate. The back side is where the
factory gauges used to plug into the printed circuit. I trimmed only what was necessary for fit. The printed
circuit was modified by cutting it off just after it makes contact with the printed circuit connector, leaving the
printed circuit running the SES, choke, P-brake, and high beam indicators only. The loose ends of the
printed circuit were taped off using black electrical tape to avoid any shorts.

I wired the Tach to my MSD6AL tach output and depended on my Chiltons manual for identifying
the wiring at the printed circuit connector. After identifying the wiring I tapped into the factory wires coming
into the printed circuit connector for the dash lighting, blinkers and fuel level sending unit. The rest of the
wiring was at the fuse box, using the empty ignition slots to power all the gauges.

The factory speedo had a Vehicle Speed Sensor built in, which tells the ECM the vehicle speed. This
allows the torque converter lock up to be engaged after the factory set speed is reached (other factors are
involved with TC lock up, but that's all you need to know for the install). In order to keep the ECM happy
I bought an aftermarket VSS unit from Stealth Conversions (1-510-462-3619 talk to Mike on Tuesdays
5 - 7pm pacific time) which I installed in line just under the brake master cylinder with my 2 piece speedo
cable. The upper half of my two piece cable needed to be replaced to fit the Auto Meter speedo anyway so
adding the aftermarket VSS was no big deal. Wiring three wires into the ECM is the last step to adding the
new VSS. If you're not running the ECM anymore you don't need the aftermarket VSS. I really have no need
for it either since I'm no longer running a lock up torque converter. I really got it to keep the SES
light from coming on.

To finish it off I simply reinstalled the black trim, with dash plate and gauges attached, tucking the
excess length of wire behind the assembly.

I'm sure I forgot some of the things I did to get this set up to work..

Tom McCoy
'86 MCSS - TNT
(TNT523 at
MCML proud member (
NMCOA #13557

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