In this google reference... one can count the four diodes needed for something to be called a full wave bridge rectifier...
I supposed more could be added... but a diode is only a one way valve...and it only takes four of them to deal with an ac sine wave to make it dc.. ..... unless placed backwards and used as a clipper of overvoltage (spikes typically)....

https://www.google.com/search?q=full+wave+rectifier&biw=911&bih=438&tbm=isch&tbo=u&source=univ&sa=X&ei=y2ytVOabJcSzggTWtYGADw&sqi=2&ved=0CB0QsAQ

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html