64 Plymouth Barracuda new switch yet headlights still won't come on

Replacing a frozen headlight switch restored parking and dash lights but not the headlights. Headlamps light when wired directly to battery -- both high and low beam. Have cleaned all gang connectors under dash and at fire wall. Checked and cleaned fuse contacts and confirmed conductivity across the glass under-dash fuses. Any suggestions? Fuel gauge is also not working with a new in-tank sender unit -- I don't know if the problems are related. Thanks for any help.