Ignition switch
I recall getting an ignition switch for ~$11 on rockauto for my 64 & 65. It is easy to change since in the dash, not like later cars (in steering column). If your factory plastic connector at the switch is melted, you could use individual spade terminals, though I am sure you could get another connector housing cheap at a junkyard or someone here. If your bulkhead connector is melted, just run wires straight thru the melted terminals. New cars do that (i.e. no connectors). Better is to get a 65 bulkhead since it has dedicated buss lugs for the big ALT and BATT wires. I did that for my 64, but you need to make the square hole 3/8" taller.