Another bridge was built to carry the loop over the lower level as shown in this photo. This was made from Masonite hard board that I originally got to use for curved fascia and sky boards. I had never worked with this material before and am impressed so far with what can be done with it.
The space in the turn around loops will not be wasted. I have had a lot of success mounting Tortoise turnout motors upside down and off to the side of the turnouts. I plan to use some of the area in the loop for this purpose. Next steps will be to seal and paint the remaining exposed areas.