W116, Rust Repair

Kent:

Just purchased a 1979 300SD with a great engine and body, but a trashed interior. Windows are not moving, switches for windows have been removed and just dangling (someone was obviously trying to diagnose the problem).

I have ordered your interior manuals about dashboards, etc. However, where can I find good replacement parts. Suggestions for sites? Also, how about exterior parts (i.e. like trim, etc.). Any suggestions on where to find those types of parts.

Also, do you have any guidance on troubleshooting the 116 windows?