[VetteVet]

Sounds like you have a large short some where in the primary circuit. Did a battery cable get against the exhaust pipe or header and burn the insulation off? You may have burned out a fusible link. This will cause the no power problems you're having.
A visible inspection should show where the short is and you need to correct this first or it will just repeat what happened. The s terminal is for the starter solenoid and and is purple as was said by cdowns. The R terminal is for a straight shot of 12 volts to the points ignition coil and would be connected to the + side of the coil. It is not needed for the HEI as was stated. The resister wire from the key to the coil is for normal running and steps down the voltage to the Points ignition coil. Not needed for the HEI dizzy. It is a orange/purple or white wire in the stock harness. You can cut it out of the harness or just tape the end off where it connects to the coil. HTH