Professor,

I wrote a DIY for my 1998 528i OFH gasket and you can see it below:
1998 528I Oil Filter Housing Gasket & “Freeze Plugs” Repair (E39) - Bimmerfest - BMW Forums

It is much easier to replace the Vanos Oil Line when doing the OFH gasket.

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1998 E39 528i 5sp MT
2006 E53 X5 3.0 6sp MT