I think you already have the hard work done. :)
If you have it working on the 4000FLX, then the 3003 and 2003 should be simple tweaks.
All of the data for movement and rotation should be identical. They just have different Firmware ID codes and # of supported buttons). Same with all of the Magellan models.
I have been working with the guys behind Spacenavd, the linux driver for spacemice, to get all the ID codes and button mapping done. The only ones that they do not support (yet) are the SpaceOrb360, the SpaceballAvenger (hard to find) and the Spaceball SpaceController. Those three models do not use an initialization string like the other Spaceballs and Magellans do.
Good luck with the kits!
[color=#BF0000] [b] [url=http://spacemice.org/]Spacemice[/url] -- Input Devices for a 3D World[/b][/color]