Dave, Yes, I have trouble envisioning building placement and how much room they will take also. Then you think it will fit and overhang from the longest car or cab roof hits the corner of a building roof, and the building doesn't fit. That's why many folks make cardboard mockups then build to suit the location. Well, I have a bunch of buildings I want to use. Cart before the horse. 
William, For one, as my arthritis, both rheumatoid ans osteo gives me more trouble, I just don't want to fool with access hatches. Second, the serpentine down the mountain doesn't resonate with the Blackwater Canyon where the grade doesn't double back. I was having trouble envisioning a couple of scenic areas I mentioned months ago. That said, the steps you outlined are good, and the plan is to start building on the end at the bottom of the drawings in January. Please stay tuned! 
I always appreciate your encouragement! 
