Maybe I'm a little "over the top" here, but... :idea: ...
have you thought of borrowing a page from the late 1990s and using a crank-triggered setup from a V6, then install the coils on each plug, like those do?
At worst, you would have to install the magnets in/on the balancer.
I only bring it up because it's so clean and the junkyards around here are full of them...