Mercedes Benz repair: fuel pressure, mercedes 300, fuel pressure

Question
I want to know what the fuel pressure should be on an 1978 Mercedes 300 D?  Thanks

Answer
the w123 fuel pressure is regulated by the alda screw check this out
http://www.benzworld.org/forums/w123-e-ce-d-cd-td/1508263-idle-speed-alda-adjust...
but as far as psi 75 or 5 bar to the distrib
http://www.benzworld.org/forums/w123-e-ce-d-cd-td/1276190-shortage-fuel-injector...