Not sure the exact date, but sometime in the seventies the gov’t. declared that all cabooses had to have safety glass in all windows. Rather than re-do all their windows, most railroads just did the cupola or bay windows and the end ones, and plated over the other ones.
Roofwalks were banned from interchange service in the mid-sixties…but cabooses usually weren’t interchanged, so they weren’t really covered. Some railroads removed them, I think some just left them in place until they retired the cabooses.
BIG aerials (for radio) were used on some cabooses in the fifties (or maybe very late forties), such as PRR ones. By the sixties/seventies aerials were much smaller and almost unnoticeable.
Well, on any railroad that assigned specific cabooses to specific conductors/crews, they crew would usually create some attachment to their caboose to help them find their cabooses on the caboose track. Often this would look like a windvane sticking off the cupola, with a dog or horse or star or some other figure or pattern cut out of sheet metal. About the last RR to assign individual cabooses were the CN and CP I believe in the 60’s.
ATSF had some semaphore gizmo’s on their cabooses pre-radio (on the front of the cupola)to allow the conductor in the hack to signal the engine crew - is that what you’re thinking of??
DIRT!! Those white SOO cabooses that ran past my house in the eighties were a mess.