Ok heres a Tutorial on how to add John's ''RDR1'' Hair into your game.
1st go to any shop_items.ymt ur using , then search the ymt for 0x8999FB88 
and replace all drawables related to 0x8999FB88 with <drawable>hair_mr1_032</drawable>

If you play with JMRP Outfits i could provide a already edited shop_items.ymt but I'd have to talk with AfroBandit 1st

and now the Tutorial for the rest of the mod: 
just put the ytd/texture files from the Cowboy Folder into ur lml stream folder