http://www.superturbodiesel.com/std/ip-full-load-adjustment-procedure-for-mw-pumps-t-189.html

There is a write-up there that shows pictures of each and explanations. It is actually a guide for turning them up a bit for more power but it should explain well.

I believe 617 engines have the MW Pump, and all of the 60x engines have the M pump.

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1987 300TDT - 195,000 (Original #14 head)
1993 190E 2.3 - 105,000
1981 300D - 250,000