Hello Ken,
Thanks for the AR file. In the meantime, I started fussing with the 5 x 17 that was based on your 5x15. It too was remade using o-72's. My problem was the O-60's take up so much room and I just cannot swing it. The 'Train Room' is in the furnace room and this furnace is just in the wrong spot!
Here is my 'mash' of the 5x17 - with your outside passing loop like you have on the 'Almost 5'x12' layout.
It made it longer, but narrower.
I forgot about the fact I asked you - it was early - I really like that outside passing loop - verses the long sweep of the O-60...