A small question about Ocarina of Time

[MNK]

First a quote
from http://www.zeldalegends.net/emulation/dumps/zelda64/
The American and Japanese versions of OoT are actually both contained in the same ROM. Accessing one or the other is as simple as changing the country code in the ROM's header.

Now a question: How to do it ? I mean what could be meant by
" changing the country code in the ROM's header ".
I suppose that it has to be done by using a hex editor,
but what exactly has to be edited ?

 

[gokuss4]

i think you can change it from the cheats in the emulator. in pj64 because it says something about "access jap version of zelda" or something like that... i cant remember.