Lifter replacement W126 560

After a recent head rebuild on my 1989 560SEL a couple of the lifters on the passenger side (my car is a RHD) seem to leak down and clatter after the car has sat for a reasonable period, say a day.

On a cold start the lifters take about 30 seconds to go quiet and then the motor is silent. The local dealer who performed the head rebuild recommends replacing all the lifters as diagnosing the noisy ones is quiet difficult and the extra labour to do the whole motor is not significant.

My questions are, does anyone just do one bank of cylinders? After having the head milled/planed during the rebuild will the shims need to be altered when I install new hydraulic compensators?

Cheers
Matt.