The reason I asked about track radius is because your mainline track at the front of the table appears to be about five or six inches from the front edge. If you're using O-54, will you have adequate track clearance at the rear edge of your 5-foot (60-inch) table? I have an Atlas O-54 track loop on a 5-foot table and the track centerline is only about 3-inches from the front and rear edges of the table.
MELGAR