A member named polymer had a post on this sometime back. If you go back a few pages or search his name, you should find it. Somewhere by his name, he had a website with some info he put up on it that had some info for this. I will see if I can dig it up too.
Found his site
http://polymer52.webs.com/motorcyclediysinfo.htmLooks like a lot of links to other sites. I did not see anything though pertaining to auto coils so it may have been in a different post of his.
You may try emailing him and see if he responds at all.
The ride IS the adventure. The destination is just to get gas!