Ryan,
some food for thought on this, not saying that it is applicable to the Grande though.
Advertising or dedicated service (placard) painted sign.
[
c-sng-discussion-forum.41377.n7.nabble.com] and rest of the thread.....
[
coloradosouthern.blogspot.co.nz]
and the follow up [
c-sng-discussion-forum.41377.n7.nabble.com]
interesting to note the scrap train on the Clear Creek line had a Boxcar placarded both sides in the short train.
[
digital.denverlibrary.org]