Basically all of the key chassis, Nervig and other owners took the CDs and created an online index for them, so that the CDs can be navigated much easier by topic area. You can get down to individual job sheets rather than having to wade through the normal MB CD BS. No copyrighted info is on the site, just a listing of the headings and subheads of the CD organization.

http://webwench.net/w123manuals/Service/Library.html

Cheers,
Gerry