How do you delete extra skins from a playermodel

Hey I’ve got a workshop model I want only 1 skin of. Its this model: http://steamcommunity.com/sharedfiles/filedetails/?id=781541855 and I just want the 4th skin (number 3 starting count from 0) I tried to edit the model by decompling the mdl file and changing it but it just fails miserably. Any help would be appreciated. Thanks