duster under dash wiring help

just got a 1974 duster sb v8 car...rock solid cam from California....rolls over but wouldn't fire...checked spark and it comes and goes...checked wiring and found splice at fire wall...tried to reconnect them and heard/smelt/saw a spark pop from the drivers side under dash....found a bare open circuit board with 2 plugs..long/skinny...and a burnt resistor or such on the board....now car will do nothing at all....what is this circuit board for and can it be bypassed...thanks in advance