If you are having issues getting stat changes to stick make sure to increase item level as well.
[Data 1 - Character 1 Bag 1 Equipment 1 Weapon L255]
0000A696 000000FE
[Data 1 - Character 2 Bag 1 Equipment 1 Weapon L255]
0000C866 000000FE
[Data 1 - Character 3 Bag 1 Equipment 1 Weapon L255]...