As far as I know, the Rapido switch stands were modeled after New Haven prototypes (although many railroads used them). I have a 17C in my front yard, which is almost identical to the 17B. I'm pretty sure that the one Bill has in his front yard is the 31B.
They do operate (rotate), provided you use the Rapido electric switch machines. I've been fiddling around with them to try to get them to work without a switch machine, since I don't use them on my layout. In the end I determined that for now, it's too complicated for me and I'll be installing them purely as scenic elements, and as such I'm assembling them as non-rotating.
To that end, I de-sprued 144 sets this week and am assembling them around 10-20 at a time. I'll have a blog post in the near future about the process soon. In total I'll assemble 288 of them, then get to painting...
Note that while 3 stands are included in each set, there are only two lanterns and one set of targets. One lantern has the day targets (typically used in yards) and the other does not (typically used on the mainline). As far as I know, both of the tall stands should have the brass targets applied as well. So you effectively get one short and one tall stand out of each set. I originally considered assembling just the staff and making a decision as to which one to use later, but the stands themselves are two different heights. I measured mine (the shaft from the top of the mechanism to the top of the stand is 43", but haven't had a chance to measure the model 31 yet to see if it's the same.
What I haven't determined is whether there was a difference between when they used either of the two tall stands, or if it was just a matter of when they were installed. For example, was the model 17 tall stand used where appropriate in yards, and the model 31 used on mainlines?
Examples of both can be found on the Valley Line and the Naugatuck Line, and I'm sure the Shoreline too. I haven't taken the time yet to see if there seems to be some pattern of usage on those lines, but of course many of them might have been changed over time.
While the lanterns are non-operating, the New Haven by rule did not light the lanterns by day. I'll paint the lens a bright silver, then a layer of a transparent color ink to provide an appropriate look.
For more information, Marc Frattasio posted a fantastic page of information on the lanterns here:
The lanterns provided match pictures 3, 4, and 5 from the top.
Modeling the New Haven Railroad 1946-1954 | http://blog.newbritainstation.com