Unless you have excessive blowby, chances are all you need is the valve job -- remove head and inspect cylinder walls. If you can still see the factory honing marks, leave it alone. My M103 has 220,000 miles (not kilometers) on it, and is still fine. Valve job at 160,000 miles. Very likely you will not be able to detect wear in the bores.

Valve guides are shot, replace as a matter of course. Springs will need to be measured -- if any are below height specification, replace them all. Replace all the lifters and inspect the rocker arms -- if any are dubious, replace the lot.

Cylinder bore to piston clearance is quite tight on these engines (0.001", don't know the metric spec off the top of my head). You will not need to balance the pistons or rods, it's done already. Mahle pistons will be well within the tolerance of 5 gr difference anyway.

Unless you've run it out of oil, the crank will be fine, probably won't even need polishing. Oil clearance on the bearings should be on the small end of the tolerance for longest life.

Valve to guide clearance should be nearly zero -- MB guides and valves are very straight, so if the oiled valve will go into the guide and the spring will return it to the closed position, clearance is correct. Do not, under any circumstances, provide more than 0.0005" clearance between new guide and vlave, it will shortly start burning oil.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!