I assume you are talking about the "rnglights" <kuid:138423:502> on the C425's?
RRmods' old freeware does have them, for example the PC GP38
http://rrmods.com/downloads/locomotives/pc-gp38.cdp.
I guess the other versions on the same page
http://rrmods.com/loco5.shtml as well.
Obviously I forgot to add that link to the description field... sorry for that, I will do for the next update. Or replace them (some time ago n8phu was talking about having a substitute in the pipeline).