I'm interested in that little bit about smash bros music timing being different on a JAP console with PAL PIF (and starfox not booting).
I thought that all that differentiated NTSC from PAL n64's electronically, apart from the video DACs, was the PIF, but it seems that's not quite the case.
That may make me forget about trying this myself unless I have many spare consoles someday.
Anyway, about the passport3, I want to advice you not to experiment much with it. Mine died recently and left me without the joy of playing my NTSC conker's bad fur day in color

It happened attempting several bootcode combinations to run my PAL Perfect Dark cart with it on my PAL console. Pointless? not quite. I wanted to see if the device could defeat PD's protection to know if it would allow me to play a NTSC version of the game.
Well, the result is the passport is dead now.
If anyone knows a way of resurrect it i'll be happy to hear it.
I have an action replay and heard some shady procedure about resurrecting "dead" or "semidead" AR/GS by plugging one on top of the other and performing an update through parallel port on the AR/GS on the bottom (which is the one that loads, after all) and if you are lucky, the update will also affect the upper one resurrecting it.
I thought that, with my dead PASSPORT3 and two AR/GS I could, perhaps, try a convoluted experiment, plugging a working AR with parallel port in the console, and on top of it, my dead passport with a proper boot cart. With that setup, I would update the AR with the passport's firmware (i think it's available somewhere), which would hopefully resurrect it, but at the same time would kill the AR, as it would have an incorrect firmware (or maybe would make it a simple passport, but useless without the boot cart slot).
With the SECOND working AR/GS, and the dead one on top of it, I would perform an update again, this time with the actual AR/GS firmware, hopefully resurrecting the killed AR.
Quite convoluted and risky, I guess.