Misc new nVidia help?

[iluvfuzz]

I've read you can't have the same nnid on multiple 3ds. I recently did the 11.1 hack that had system transfer. One of the 3ds has my network id. What I want to do is make my husband and idea on the other 3ds. How do I do that? Backup nand, backup sd, format, restore nand? Or would that just put the same nnid back on it?

Ugh my tablet keeps changing nnid to Nvidia.