I've always wondered why there isn't a site with ring lists for pins or why it isn't added to IPDB or one of the flyer sites. Or is there such a site around?
Sure is.
http://www.flippers.com/rubber-rings.htmThe added bonus of the above website is that incorrect listings from the manual are reflected in updates from pin owners. The Getaway entry for example has the 5/16 rings listed that the OP mentioned were missing, which the manual doesn't have listed.
