Download the Heavy Maintenance Manual (https://www.rotax-owner.com/pdf/MMH_912_914_Ed2.pdf) for the wiring diagrams.
I converted my mid 90s vintage 912UL (with Zipper Big Bore) to the new style 6x6 ignition boxes with the soft start feature. I needed to replace the original boxes and they had a lead time in the range of years...
Read through this thread for what I did including a parts list. https://teamkitfox.com/Forums/thread...light=ignition