ROM Hack Question ALCNF

[DeoNaught]

Hi I want to make a RomHack/Modified version of animal crossing
New leaf as in an Installable .CIA file.
and I was wondering what program(s) I should use?
I wanted to change where some stuff is, and textures.

 

[Roomsaver]

https://gbatemp.net/threads/tutorial-how-to-decrypt-extract-rebuild-3ds-roms.383055/