Water Temp Gauge help

[MattyBs71]

Hi all, I just bought a 71 C10 SWB. The truck came with aftermarket gauges, I picked up an original cluster from Ebay and need help with the Water Temp gauge. It has 4 prongs on the back, what is supposed to hook to what, I know one should be ground and one should be from the line from the head on the engine, what are the other two prongs for?

Also if looking at the cluster turned over what are each prong supposed to be.
Am I right with at least the first two?

Example

Left prong: Line from engine
Right Prong: Ground
Top prong: ?
Bottom prong:?

Please help!

Thanks
Matt

[MattyBs71]

Originally Posted by MattyBs71

Hi all, I just bought a 71 C10 SWB. The truck came with aftermarket gauges, I picked up an original cluster from Ebay and need help with the Water Temp gauge. It has 4 prongs on the back, what is supposed to hook to what, I know one should be ground and one should be from the line from the head on the engine, what are the other two prongs for?

Also if looking at the cluster turned over what are each prong supposed to be.
Am I right with at least the first two?

Example

Left prong: Line from engine
Right Prong: Ground
Top prong: ?
Bottom prong:?

Please help!

Thanks
Matt

I figured it out today on my own though, no wires hook up to the back of the gauges it all goes through the circut board, I was also able to find the green temp send wire. Also found on here if you are going from Idiot light gauges to real gauges it isn't just a plug them in and go type thing you have to move some wires around in the instrument cluster harness. If anyone else needs to do as I am here is the link (copy and paste) I found at GMCPauls site that kicks ass and will help me out immensely! http://www.gmcpauls.com/Tech%20Tips1.htm