i think i got it, thx to gimp.
contline.tga in stock is a full whietish line.
gwx contline.tga is a partial blackish (left part missing)
so i've already created a new one by having stock's colors tured black, i think that'd be an all grey in game.
i am still working meanwhile i'm bkping sh3+gwx to be able to uninstall it inorder to install a stock version for testing, too much loading time in gwx to wait.
tricky thing'll be to get colored sound contact lines with grey coursetails
