That wire should be a "resistive" wire. Other automakers used a fixed balast resistor mounted to the firewall. GM used a special type of wire with (higher than normal) resistive properties. This is generally there for saving the points from burning if the ignition key should happen to be on, with the engine not running, and the points were closed. Also, I think this is fused. The fuse should blow before any wire burns out, even if someone had replaced the resistive wire with normal wire. Anyway, it is possible to install a fixed ballast resistor to replace the resistive wire. Can't help you to locate one except to say that there was a thread (quite) awhile back on this. The ignition system on these cars is pretty simple.
Phil