Wayne,
Are you going to install spikes to the rails?
I was going to purchase some HO flex track, Tie sized wood, .025 aprox, and cut the sticks into the appropriate tie length. Then remove the track from the plastic ties, glue them to the new wood ties, at the appropriate gauge. I was then thinking of cutting off the spike plates from the old flex track ties, and gluing them to the new tie/rails.
With the Trumpeter WR360 and the Hase Thor, I'm thinking it should come out to around 2'. I can't imagine the size of your setup. The K5, flatcar, AA, BR52 and did you say a generator? That is going to be EPIC! do you have the room or are you going to send it to the Smithsonian for display?