I'd be chasing the source backwards from the distributor that has not spark, HT lead, coil, wiring to the coil, power and trigger signal at the coil. If no signal, wiring from ECU, cam angle sensor. Not hard to do if you you have one working side to compare with. Just need a volt meter and test lamp. You could start by removing the HT lead from the bad dizzy's coil and fit a spark plug lead to the coil, run the lead to a spark plug earthed against the metal body of the engine, crank and check for spark. Good luck.