I'm looking for input on what type of sanding tower would be appropriate for a late 40s era mid-sized engine yard. Some pictures of available models, like Weaver's, show them next to a diesel. Thanks.
You might try a Google search for "sanding towers" or "steam era sand towers", as there is a wealth of information available. Plus, many sanding towers from the steam era, were still being used during the early to mid diesel era.
Lastly, in my opinion, the absolute best looking sand tower for a steam locomotive terminal was produced by Max Gray. I purchased mine off eBay, many years ago, but I believe that American Models (do a Google search for their website) now offers many, many brass, steam era locomotive servicing structures.