How reliable is the distributorless ignition system on a 1990 King Cobra 350 Chevy ?
Do the flywheel sensors go bad ?
Can I remove the rubber plug and install conventional ignition ? There must be a driveshaft to turn the oil pump.
I really try to stay away from anything except Merc inboards and Merc I/O's

That ignition is very releiable, plus it has a knock system built into it. The plug your refering to is the oil pump drive shaft, if you take it out the bottom looks just like a distributer. You can just pull it and add a distributer, and coil system but I would stay with that stock system...

If this thread can be resurrected... I have this same model year setup (1990 OMC King Cobra 5.7) and I need some help tracking down replacement coils and sensors. I have been searching for a year...

iirc you can't buy much for that old ignition ..Since it is a chevy motor you can always convert to? ( lots of choices ) How about converting to Merc Thunderbolt. Cheap and EZ