im sure the poster of it on our site has no problem with this so just edit as u wish
main chat box C:\Program Files\Rockstar Games\Gta san andreas\MTA\datafiles\imagesets\chat.png
small chat box C:\Program Files\Rockstar Games\Gta san andreas\MTA\datafiles\imagesets\chatinput.png
main menu C:\Program Files\Rockstar Games\Gta san andreas\MTA\datafiles\imagesets\background.png
May differ depending on where u have installed gta