RIR or Red Star?

[HeadHen]

I ordered all pullets from MM (I am sure some roo's will have snuck in too) and I'm having a terrible time telling which ones are the 5 RIR and which are the 9 Red Star. No exact numbers of easily identifiable matches. I've got 4? that are a much browner red and the rest are all kinda the same yellowish red.
Any hints for characteristics on new chicks that might help?

 

[MissPrissy]

My red starts males feathered out white and then developed red and brown splotchy feathers down the saddle.

 

[tiki244]

RIRs are very dark!

Mahogeny colored