I am having issues on a 98 S-10 Blazer 5 speed.

Backstory
Recently replaced the heater core in my truck. After putting back together I am having issues with half my gauges not working.

Problem
Fuel gauge, Temp gauge, Speedometer do not work.
Odometer lights up but does not change
Battery light and low fuel light stay on.
Tach, Voltage and oil pressure gauge work with no issue.

What we have done so far
We tested the cluster in another truck and all gauges work with no issue.
We tested the BCM(Computer just above and to the right of the gas pedal) in another truck and all work accordingly.
We confirmed power to the pink wires(A7,A8) that plug into the cluster harness.
We confirmed the ground going to the cluster is good and making the connection.
Checked fuses and confirmed they are all good.



Everything we have found says it's either the cluster or a ground. We have confirmed the cluster is not the issue. We are now stuck and not sure where to go from here. We don't know if there is another ground that could be the issue that we need to check; or if there are other wires that we need to track down.

Any help that can be offered will be greatly appreciated.