I haven't looked very deeply into the MSD solution (we run the stock dizzy and ignitors), but I'm curious how it would work if there's no e-shaft angle sensor. The 12A normally uses the pickups in the dizzy to tell the igniters to fire.
If the dizzy holes are welded over, they MUST have had some other way to trigger the plugs, maybe a later model angle sensor or something. If you have that, you can run the MSD option. If not, like Erik stated, you could re-isntall both dizzys and their associated ignitors and coils, which I think would be the simplest way (especially if you can find the parts for cheap). If both motors are in-phase (both #1 rotors hitting TDC at the same time) you could probably just use one of the dizzys to trigger the ignitors, but you'd need both for spark distribution. If they're out of phase, you might be able to get away with the same setup (just swap #1 and #2 leads if they're 180 degrees out of phase), but for simplicity's sake maybe use both independently for both triggering and spark.
Basically, unless you go with a fully aftermarket ignition, I think you would need two full systems (2 dizzys, 4 igniters, 4 coils, plugs wires, etc.). But this is my first rotary car so I could be way off base; I'm sure the pros will correct me...
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