Unless you actually need the extra 512 bytes, you should be able to use SHIFT-UPLOAD (or "SKETCH/"Upload using programmer" without having to modify boards.txt at all (assuming that you've set the TOOLS/Programmer and Tools/Port correctly.)
Unless you actually need the extra 512 bytes, you should be able to use SHIFT-UPLOAD (or "SKETCH/"Upload using programmer" without having to modify boards.txt at all (assuming that you've set the TOOLS/Programmer and Tools/Port correctly.)