John and Broth, I really am overwhelmed by your efforts to find a solution but I should explain that I want to keep it simple, within reason and not turn the entire shed into something resembling a Scalextric set. As much as I admire your efforts, railways ran from A to B. I have many ideas teased out and just this morning started marking out another possibility. All the time in the world to plan and tweak, until its time to start laying track. Thank you again.