Hi Stefan
I looked at doing this a Pazon system using the trigger unit that fits the distributer as the trigger unit for them is smaller, designed all the bits and started thinking about Pazon Smartfire crank triggered unit so went that way, machining was a lot easier, fits nicely and so far all good. I have posted information on my 650SS Build.
I put the shell of the magneto back in place with no internals.
Regards
Burgs