I am no expert on US markings, but from what i can tell, certain FG's had certain colours. But not all FG's did it, just as not all BG's had coloured tails. I know Bodney used Blue noses, and there was a Yellow nosed FG and of course Green for Wretham. Not sure about any others.
I guess buying loads of AM for a 5euro kit is a bit silly. But i am sure you can do a nice job on it.