When we ran the rotary, the lead engine had white flags and class lamps.
Concerning the D&RGW use of flags and lamps, in the late 50's there was a directive handed down annulling the rule requiring flags and lamps. Occasionally, you'd find a fan trip out there with flags, but rarely. I imagine that ruling kept the Grande running flagless to Silverton....
But.....when the Silverton train ran in sections in 1964, someone made a big deal out of getting green flags made up. You see quite a few pics of them. When the Grande added trains 463 &464 a year or so later, the flags disappeared.