I have a 1967 Pontiac Bonneville. I attempted to give a jump and after insuring the jumper cables were connected properly a few seconds later both cars started smoking and the jumper cables begin to burn. On the Bonneville smoke was coming from the wires and alternator. After removing the jumper cables I tried starting the Bonneville and it wouldn't start. I changed out the starter and checked all wires for burns and melting, on the Bonneville, and found a small portion of a wire (I don't know which wire this was) that had burned and melted, I covered it with electrical tape. Then checked all wires again thoroughly, along with someone else, and found nothing else. Then I tried connecting the positive terminal to the battery and still sparks and heavy smoke. I disconnected the wires from the alternator and connected the battery completely and there were no sparks, and the car started. But the alternator was not connected. There was a eye ring wire that was connnected to the alternator, I touch the alternator with it and it sparked badly. I changed out the alternator and it's still sparking.

Please help, I'm extremely exhausted and out of answers and troubleshooting. Please, please, please help me.

Many thanks in advance.
SSL

What was the original reason for the jump, just a dead battery?

You are on the right track. Your car has only 3 devices that are not protected by fuses: starter, alternator and voltage regulator.

You have changed two of the three so IMO you need to inspect the voltage regulator.
Please note most people these days are not used to GM cars using an external regulator. They went to a regulator built into the alternator in the 1970 model year.

BTW that melted wire section that you covered in tape may be a fuseable link and will need replacement in order to function properly.