i cked r&ms web site they do not sell that cap ???the lights are half way down on the side and are cut into the rear cap!
You might want to call them to be sure. It looks like R&M carries three different rear caps for 4905's on their website but don't show photos or have detailed descriptions for any of them. So it is hard to say what styles they are.
http://www.rm-fiberglass.com/bus/model/46.html
Call Richard at R&M Fiberglass, I'm sure he will make whatever you want.
Paul