611's cab gauges

The air brake gauges, and probably some of the others, require regular calibration.  The gauges wear and new gauges may have been required to allow proper calibration.  Gauges were collectible and they should nave no trouble finding period gauges if they wanted them.

I don't think so. Remember that N&W 611 is a pretty "new" steam locomotive and would have many on the latest gauges available in the 1950s, including 24RL air brake schedule. I seriously doubt if anything in her cab was, or has been, replaced with "2014 era gauges".

The air brake gauges and steam pressure gauges require annual certification.

Our engine used period gauges, but they do indeed wear out. I had to buy new gauges from Ashcroft. They work great, but boy, they sure are ugly!

EDIT:

I asked a buddy who is helping with the restoration, and who used to be involved with the program back in the 1980s/90s.  He says he's pretty sure the gauges have been updated since the old days.  What is in there may be the most modern from the steam era (he's not sure) but he's pretty sure they aren’t original.  He believes the air flow indicator, speedometer and boiler pressure gauge are all modern. He's going to ask for more info which I'll pass on if I can.

In my experience, the air gauges rarely match each other on any locomotive more than a few years old, since, if one fails periodic inspection, it is typically replaced with a rebuilt one from the supply bin in the shop.  Gauges needing repair are put into the bad order gauge bin, and, when there is an accumulation they are all sent to the bench for repair.  It's easier to do that in quantities, rather than everything being a single job.

So, there are often gauges from different manufacturers (Salem, Wabco) of different ages on the same locomotive.

Should I say anything about the radar speedometer in the 765?