Well on this wpy style caboose,
The round molded in lamps with dummy white reflectors were in fact the white spotlights. The light on the cupola was a rotating beacon.
On later versions of this caboose, lgb added US style separate lanterns. They offer their own charm and ease of inserting the lgb brass socket and 18v yellow bulb.
While speculation, i would think the roof lantern, being amber and very bright would penetrate snowing or blizzard conditions better than red. Probably a good thing if stopped for a blocked tack.
I lighted the spotlight lamps on mine. I used two lgb 5v reds wired in series. They are vivid and look great. I simply set them into the round housing, without an lgb style 5v plug.
My roof lantern is a flashing amber led, runs off AA , i think 2.
If i were to do this now, id make every lamp an led. A pulsing led, (grows bright and then dims) similar to a light house style might be perfect depending on the pulse rate.
but, drgw only ran cabbose lanterns, and nothing that resembles the lgb wpy model. So, you can apply rule 8. In so doing, let me say bight blue LEDs , perhaps for the cupola light, would look very good,imho. (Did this on one of my 2033s that blew aflasher circuit, they look great).
Have fun. Lights are good!