The colors show that most of the base/flat level track is now O60 - running O54, with the gray track color. The red track is the last of the O36 diameter, on the spiral loop passing track. The regular brown ties are O48-limited, even through the turnouts are O60 and O72.
The elevated branch and loop is all O48-limited.
I regret giving up most of the yard to complete the O60 loop, but perhaps that is worthwhile in being able to run O54-Legacy locomotives, and to have the additional operating patterns thus created.
