This is a "shoe-box" layout; the box is 14.25 in. x 10.5 in. x 4.75 in. with a 17.5 in fiddle-yard off scene.
The thread is here: viewtopic.php?f=1&t=8665&p=110635
There is also more here: http://www.railroad-line.com/forum/topi ... C_ID=37211
A better link than the one in the thread above.