Need help with cluster

[ethankane]

I am almost done with my 71 c10 after two years of work (with a lot of help reading this forum) I an getting the electrical back together inside. I installed the cluster and hooked it up.
All seemed good truck fired up headlights and dash lights work.
Only problems were
Fuel gauges pegged past full with only a couple gallons of gas.
Temp gauge pegged.
No temp light when the key is turned on.
So I read the forum grounded the bottom peg on the temp gauge still nothing there.
Ran entire new line to fuel tank because if I ground the line it worked. Still nothing.

Then I was testing the cluster with an electrical tester.
When I check the #2 wire on the plug there is barely any signal through the tester but the temp light comes on with the key on.
When I check #4 same dim light on tester and the fuel gauge works.
Then if I hit the top peg on the temp gauge same dim light and the needle moves on the gauge.

What an I missing. Any help is appreciated.
Thanks