go on ur profile, search the current name one of your custom classes has and just edit the class name u have, calc blocks/ rehash & resign or w/e & put back in ur HDD
Yeah, you just need to search for the class name in HxD and overwrite the part you want the colors or buttons in with "^1/^2/^3/etc." or for buttons type into the offsets "01 or 02 or 03.." it depends on what buttons/colors you want. You can find all of them on the mod your GT tut.
Then rehash and resign in modio and re-inject back into your HDD on xport.