I'll have to check on the flywheel diameter, but IIRC it takes a 10 or 12 inch clutch. What is needed is a 168 tooth ring gear. The geometry of the existing teeth is wrong and it isn't 168 tooth. I don't recall, at this late hour, what the tooth count is, but it's not a case of being able to simply heating, removing, and flipping the ring gear. As I understand it, the flywheel/ring gear sits too far "back" - for the starter to properly engage, never mind the issue of the teeth count being off. And apparently there is only one bendix for that starter. The kerfluffle apparently had its' genesis in the 6v to 12v conversion. I will measure the flywheel and see if I can get engine casting numbers here tomorrow.... I need to go back and check your post to see if I covered everything.