Round gauge idiot lights to gauges swap

[Chevys_Only]

I recently purchased an '84 Monte Carlo that was equipped with the round speedometer type dash, but it has the idiot lights in place of the oil pressure, temp and volt gauges. This isn't my first G-body so I had an extra cluster that had the gauges I wanted in my dash. I didn't see any posts here about this swap, so maybe this will help someone out. I was hoping to just disassemble my cluster and swap in the gauges in place of the idiot lights but no such luck. The back half of the cluster housing is not made to accept the gauges, it will only accept the idiot lights. It also requires a different printed circuit. It isn't a deal breaker for me as I have a complete cluster for parts, but the spare cluster was blue, mine is brown, so now I have to dye the housing to use it in my dash instead of reusing my original cluster housing. It appears the wiring will not require any changes, but I am going to remove the brown wire (Pin 1) that went to the alternator and connect it to ignition power thru a resistor as shown in the wiring diagram, this will insure the alternator charges properly.

 

[Chevys_Only]

An update on what is necessary for the swap. When I got to the original oil pressure sensor, the connector has four wires on it. It is a multi-function sensor, it controls the choke heater on the carburetor as well as controlling the low oil light in the dash. I am going to have to use two sensors to keep everything working properly. I will add the additional gauge sensor along with the original sensor. It's necessary to remove the tan wire from the original sensor connector and attach it to the gauge sensor. The other wiring on the original sensor can remain the same. The coolant temperature sensor only requires removing the original switch type sensor and replacing it with the gauge sensor. The wire that originally controlled the light will now be the sensor wire for the gauge, it is dark green in color.

 

[Chevys_Only]

Swap is complete, everything is working properly, I did make one change from my original plan. The dash warning light panel has a "Choke" indicator light that isn't used on this car. By removing the dark brown wire from pin 1 of the dash connector and placing it in pin 14, which was empty, the "Choke" indicator now works as my charging indicator. If that light comes on I know the alternator isn't charging.

 

[Killerdave8813]

Sounds good! I was thinking about using the choke light on my 78 as a "check engine" light for the Tuned Port Injection but haven't got that far yet!