Ha Russ,
Yes,"mountains" are in my prototype, I'm modeling a section of the Seaboard Air Line's (later the Seaboard Coast Line)"Silver Comet route" northwest of Atlanta,set in the 50's.
This section of the route(between Dallas and Rockmart Ga.) is almost continuous cut and fill, and includes a 800' tunnel through Brushy Mtn.
My plan is to use the Brushy Mtn. tunnel to hide the return loop on the right end of the layout, and the surrounding hills to hide some of the track closest to the ceiling.
Then a small yard on the left end, inside the other loop, which would be set in Rockmart, a small town founded on the slate querrying industry in the 1840's. The quarry is still active, which will give me a industry to justify the yard and a way to hide some more of the back track.
I'm lucky in that I have total acsess to the ROW, after CSX aquired the Southern, they had two parallel routes. The Southern's was more direct than the SBL's, so the old SBL ROW was abandonded.
Enter the state of Georgia and the Path Foundation, which converted it to a Rails to Trails project that I cycle about once a week.
So guess my biggest problem is the lighting/fascia issue?