Honing angle ( cross hatch ) is supposed to be 25 degrees.
" Bore cylinders in two passes. An allowance of 0.03 mm for honing is to be left in the bores. "

Not MB but interesting...
https://www.hastingsmfg.com/Master_Catalog_Pdfs/P7-9.pdf

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/diesel-discussion/10414-help-i-need-check-stretch.html

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