Bad ignition sw. ? 99 PA Ultra

[Jagawar]

Thanks for looking My daughters 99 PA ultra. Would not start ,Cked all fuses (OK) Found batt dead (so I thought) put it on charge and all sys came up. I went to start it and turned key to "on" smoke came out of the key area. All sys. went dead again . removed batt cable and recharged batt. reconn.batt. and engine started no problem. However now the radio is dead and the gas gauge is not working.. I think it is the switch.. How do I replace it? Could harness be smoked as well as sw.? She is a single Mom with no child support and needs this car ..