Alright, I added this script I also changed it to look like this: 
 
function replaceModel()
    local skin = engineLoadTXD ( "skins/80.txd" )
engineImportTXD ( skin, 80 )
 local skin = engineLoadTXD ( "skins/81.txd" )
engineImportTXD ( skin, 81 )
end
addEventHandler ( "onClientResourceStart", getResourceRootElement(getThisResource()), replaceModel)
 
but when I start the resource then connect to the server, it downloads a file so it must be the two modded skins, I then select the team but it shows the original skins and not the modified ones? 
any help much appreciated.