Can’t start ?

The ignition switch wiring from the replacement column has a different connector than yours. That column ignition switch came from a 70-74 car. You need the 1975 switch. This difference can be seen by searching eBay : 75 valiant nos ignition switch. If you don't want to replace the switch, splice the red and black wires from the ignition switch connector to the red and black wires from the under dash main harness.