W123 cluster to W126 cluster

[eatont9999]

Hi again everyone. I'm sure this is a unique question and against the purist motto but I have to ask anyway.

As most of you know, the W123 has a cluster with chrome plated needle hubs, etc. The W123 and W126 clusters are not interchangeable due to fit and the mechanical drive on the W123. When I get my hands on a properly working W126 Diesel cluster, I want to swap the needles out for the chrome based W123 type. I think the older style are classier than the bland-looking W126 style. I am also thinking about customizing the efficiency gauge from a gas model cluster by attaching its vacuum line into the tranny modulator line. I think it should simulate the throttle vacuum of a gas engine as that is what MB designed the tranny for.

Are needles interchangeable? Can the left-side cluster pack be swapped and still maintain correct temp, pressure, etc readings to be accurate?

[Stretch]

I can't give the answers you require but you might be able to glean some information from this thread

Help identifying diesel tachometer req'd - want to fit it to my car!

I think diesel giant did a rolling back the years odometer thread somewhere - perhaps there's information in it about needle swapping...