The 60x water pumps are relatively easy, at least on the 603. The 602's I have look the same, but your 601 has a electric fan clutch that may be tricky. The gasket is paper so I used some hylomar just to make sure it'd seal. The once the fan and pulley are off its just a few 10 mm bolts that hold the pump in. I didn't have to remove the housing or alternator when I did it on my 6 cyl diesel.

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Brian Toscano