How to mod : GI Joe.
1) open your save in a hex editor.
2) refer to the image below for the data mapping. Change the values to what you want.
The image shown is from extracted data from the save, so the offset is off. Just add 'D' to the number offset to find it if the save isn't extracted.
Example : offset 000005F0 (if extracted) = 0000D5F0 (if not extracted).
3) after editing, rehash.