i went with my son a few months ago to a model railroad that had small gauge tracks similar to the CL ad.
the trains were large enough to seat 4 -6 adults in a single file line in seats on the flat train cars on 1.78 miles of small gauge track
it was real fun seeing the work and craftsmanship put into these working models
the guy messing with the locomotive, he built the engine by hand
i was impressed to say the very least.
The hand made / home shop engines are impressive. There was (still is???) a live steamers club near Perkiomenville, PA. I visited there in the 1980s with my son. I think it was over a Labor Day weekend. I'm not sure if it's still there or whether non-members can come and watch, liability issues being what they are today.
There are Live Steam Railroad clubs all over the country now. Most all have public run days every other weekend and usually welcome people to tour the back shops. Also most are constantly looking for new members who are interested in machining. I think Discover live steam dot com has a list of clubs by state. Making locomotives is a natural fit for hobby machinists! Lots of fun. Always something new to work on.