On the idea of “battery ignition”, I found these two coils that would omit splicing a “Y”
in the spark plug wires on an automotive type coil.
One is for an Onan Opposed twin, the other 2005 era GM coil packs,
which one fellow adapted to his twin opposed lawn tractor.
I wonder how long running these coils before the battery ran out of “juice”?
Prepare to be boarded!