WTF! GTFO!
Okay, me again. After a bit of googling figured out that the folder that the u8 tools puts out does indeed contain the rom. And in fact, that is literally the name of the rom. Just plain rom. No extension, just rom.
Get this, though!! I renamed it Sin.z64, loaded it into my z, but it was recognized with the original Japanese name. I thought, okay, could be, but once the game booted.... Japanese!! WTF!!
Is the translation in the (Wii) emulator itself, and not the rom???!! Man that´s wierd
(edit) Let´s say that is the case, would someone with a clue be able to pinpoint it, and somehow use it to patch the rom itself??
(2nd edit) The folder that the u8 tools spits out also contains several bin files, each indicating a different language!! Maybe the bin files can be used to "patch" the rom??