The sensor(s) are/were looking for 12v for operation. You may need to replace a lot of parts since putting 24v on the whole car's system.
The "RAW" operating voltage normally directly coming from the battery (12~14v) is usually sent directly to the sensors, alternator, starter, headlights, tail lights, fuel injectors, and the ECM. So putting 24v on those items is going to cause problems...
The ECM "might" be save-able by a good electronic tech as it's electronics uses internal voltage regulators. It depends on how it's built. I know it is protected by a reverse voltage protection diode/rectifier that is designed to fail and blow the ECM fuse so it may have other internal protections also.
You may need to become good friends with a salvage yard owner that has a car like yours that was totalled as you may need lots of parts to get yours going again.
Hind site is 20/20....