gas and temp gauge

[65truckowner]

I got my 65 c10 running today. I have a new wiring harness behind the dash and have redone the wires under the hood. My question is the gas gauge and temp gauge only move up to the empty mark and the first mark on the temp when I have the key on or the engine is running. I have a new sending unit in the tank as well. I unhooked the wire from the sending unit to see if the gauge would peg out. It just moved to empty. What is causing this. Also my new alternator is not charging. The amp gauge will not move at all.