[Robert E. Gilbert's Small Town Warehouse from the April '57 issue of Model Railroader  and REG's "bizarre landscape with tiny people and weird shapes." sourced from The Outer Space Art of Robert E. Gilbert.]
I recently read that E. L. Moore started in HO model railroading in 1953, so I thought I'd read through model railroading magazines published from 1952 to March 1955, the month E. L. Moore's first article appeared, to see if there were any obvious stories or photographs that might have influenced Mr. Moore. On one side trip I stumbled across a biographical note on the prolific model railroad writer, Robert E. Gilbert, in the July 1959 issue of Model Railroader. Here's a snippet:
His first article in MR appeared in the Apr. '57 issue, and since then he has written 22 articles for MR and Model Trains. He's also written a number of science fiction stories, and a detective story, plus "how to" articles for an art magazine. He's also sold a number of drawings and paintings.
In model railroading, his primary interest is structures - and he has a 5 x 10 ft. layout still in its earliest stages of construction in his family home overlooking the Southern Ry. station in Jonesboro, Tenn.
So, you're thinking, ok, interesting fellow, but what's up? Well, he had 5 stories reprinted in Kalmbach's 1958 Easy-to-Build Model Railroad Structures. When I got into the hobby back in the '70s I was crazy about that book and more-or-less memorized it. I particularly liked his section tool house project and built a stone (!) version. The bio released a load of nostalgia in my brain, so I looked around the internet to see what else I could find. Nothing more on Robert E. Gilbert, model railroader, but some intriguing stuff on a Robert E. Gilbert, science fiction author and much published artist in science fiction fan magazines. That second Robert E. Gilbert signed his works REG. His art is way out and you can see a good selection at the Artisans website. There are also a couple of good posts about REG at kentmcdanielwrites here and here.
There seems to be some common points in the biographies of these two gentlemen - other than name - that make me wonder if they're the same person.
REG was active from the 1950s to the 1970s in science fiction fan art. Robert E. Gilbert was active in the model railroad press in the late '50s and into the '60s . The eras overlap.
REG was a native Tennessean and was thought to have died in Jonesborough, Tennessee. Robert E. Gilbert is noted to have lived in Jonesboro, Tenn.
REG was an artist; drawings and paintings. Robert E. Gilbert was noted to have "sold a number of drawings and paintings".
REG published 3 science fiction stories: A Thought for Tomorrow in the Nov. '52 issue of Galaxy, The Rocks and Rills in the Sept. '53 issue of If Worlds of Science Fiction, and Stopover Planet (initial publication place and date appears to be unknown). Robert E. Gilbert was noted to have "written a number of science fiction stories".
There's nothing conclusive here. And the online material about REG doesn't mention anything about model railroading. But, there seems to be some strong circumstantial evidence that Robert E. Gilbert, model railroader, and REG are one and the same  - but maybe I'm just the last to know :-)
 I chose that example of Robert E. Gilbert's work only because the signs above the doors read: N. E. Moore.
 One of the most interesting of Robert E. Gilbert's articles is A changeable railroad in the June '62 issue of Model Railroader. In it he explains how to build a small layout where it's easy to change the location of buildings and scenic elements because nothing, and that includes the scenic material, is glued down. It's well thought out, and the drawings and staged photos are excellent. And it reminded me of the Sand Table described in my grandmother's manual training text book. I don't know when Robert E. Gilbert went to grade school, but maybe that's where he got the idea.
 If they are the same person, then this statement at Artisans is fascinating: "One of the most striking things about Gilbert's work is the strong sense of the alien. Landscapes are strange and unexpected." Yet, his model railroad work is the complete opposite. I'd say it had a strong sense of the real.