Gun Runner - what are the actual measurements of what you want to do? What is your proposed elevation change?
There are other ways to change elevation if needed... Logging lines would use switchbacks, so that even though they need all the track, they would not have to run all the way around a mountain to do it.
In the model world, there are helixes, train elevators, and "cassettes", that can transport trains for one level to another. So unless you need to see the train actually climb the grade through the scenery, you do have other options.
Andrew