Bruce wrote:

Vacuum system? Doors? Was the center lock operated by a vacuum
system?

This discussion reminds me of the Mercedes 600 "GROSSER MERCEDES"
as driven by Jeremy Clarkson on Top Gear. It had hydraulically
driven everything. Shock absorbers, windows, seats, trunk lid,
fresh air vent.

http://californiaclassix.com/archive/67_MB600.html

sam