Just get a diagram and check one wire at a time .Dont power the dark blue wire which is the gas gauge.Ground the harness and power the selected wires and check the functions Ive seen where wires have rubbed through and shorted out inside the bulb socket
Its not hard get a diagram + 12 volt testlght testlight And ask as many questions you need to resolve
1969 Daytona 440 L9B410772
1970 Coronet 500 383 Presently owned
1970 Superbird 440 U 166242
1970 Superbird 440 U 174597
1970 Superbird 440-6 V 179697
1970 Coronet RT 440 U 224126
1968 Road Runner 426 J 134509
1970 Daytona Replica 318 G 178701