For DB2020 you can use ImageTool. I attached it for you. Then, open the MAIN of your phone (ex: k800.mbn) and search for the icons that you want. Then you can replace them, delete some other icons that you don't need to make space for bigger ones...etc. After you finished the work just save it as a .vkp patch. You can apply it with SeTool 1.11 or Far Manager plugin JDFlasher.
Good Luck
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