Fuel gauge wire routing question

[dmack91]

Trying to get the fuel gauge working on my 1983 K20. It was originally a diesel which a P.O. converted to gas. I replaced the butchered dash wiring harness with one from a donor truck.

I traced the wire from the tank valve on the frame. It is pink has been cut off at the base of the firewall near the clutch slave cylinder (with a yellow wire that I believe is the old water sensor wire for the diesel). Can anyone tell me where it physically comes through the firewall and connects to the cluster? Is the wire still pink at that point or tan as the cluster wire is)?

I'm assuming if nothing else, I could pull the cluster again and splice it to the terminal in the cluster plug, but would prefer to find where it actually is connected to get to the cluster plug.

Thanks for any help you can provide.