TECHNICAL RESOURCES ON THE INTERNET
There is no shortage of info, manuals, descriptions etc on the web, the problem is often finding what is out there. Rather than reproduce what has already been done, I will simply link to various sites from this page - this is both less work for me and also promotes other enthusiasts' sites.
Bearing sizes page by Jean-Louis Olive
Seal sizes Page by Jean-Louis Olive
Downloadable manuals etc by Dutch Laverda Club