It isnt that simple, i played quite a bit and never got it to work. The reason i came up for for it failing was that the timing needed wasnt right which also may be the case for the other nr01 issues i was having.
the nk.bin text which is meant to be altered by the chip is set very early and executed very early too. i altered the timing quite a lot, to the case where i was too fast and it failed, and still i couldnt set to boot ly.bin or similar.
It is also compounded by the size of nk.bin as this is what gives the modchip its window to patch as it is being read and setup from hd (not sure how that changes with the new structure yet) - ie the bigger the nk.bin, the larger the window.
The only other way was to repackage as nk.bin, however with bt boxes i also coulnt set the env variabel to boot nix so a pseudo setenv area is required to be used in the loaded nk.bin