I replaced Trevor's dresses with the Veteran Jacket from Franklin.

Installation path:
\x64v.rpf\models\cdimages\streamedpeds_players.rpf\player_two *BACK UP*

Note:
There is a slight "problem" with this mod... being as I replaced his dresses the game does not let you put pants on him in the dresser/wardrobe. To put pants on you need to use a trainer I recommend this one:
http://gtaforums.com/topic/789786-vrelwip-enhanced-native-trainer/

Credit for the idea goes to Dauge
The awesome skull bandana also goes to Dauge
https://www.gta5-hub.com/player/skull-bandana-for-trevor