Models by Rockstar Games
Aviators model by retarded_chicken, Rockstar Games

Now helmets will have 8 skins at the same time. You don't need to use trainers, skins will vary itself
Hockey mask replaces glasses, which is not used by the game, you need to use trainers or mode menus to be able to wear it. Simple Native Trainer will do the trick

In 'extras' folder you'll find more colors for hats and for aviators
If you are using some trainers or mod menus, which allow you to change the glasses/hats skins, then you can just drag and drop all textures to the player_p.wtd
If your trainers can't change the skins, then just pick one and replace original texture with one you like.
Example: if you want to have purple aviators with silver frame, then you need to replace texture p_eyes_diff_002_a.dds with texture p_eyes_diff_002_d.dds (it must be named as p_eyes_diff_002_a)
Or if you want to have beige cap, then you need to raplace texture p_head_diff_001_a.dds with texture p_head_diff_001_c.dds (it must be named as p_head_diff_001_a)


Install:


Use OpenIV to edit pedprops.img (Grand Theft Auto IV\pc\models\cdimages)
Replace player_p.wdd and player_p.wtd
Defragment the pedprops.img (Press the keyboard shortcut Shift+Ctrl+R)