SNES Region Switch Mod

While reading this mod I wondered if I should follow this to the letter or not because this is being preformed on a PAL SNES, and mine is NTSC. I just want to make sure everything would work the same, especially the 50/60Hz part.

http://mmmonkey.co.uk/console/nintendo/snes-switches-1.htm

 

I've got a PAL and NTSC snes, and I did the same for both, well, schematic wise as they're both automatic running on PIC chips.
From what I remember (My memory isn't all that great) the crystal part needs to stay the same (NTSC) as using a pal crystal messed things up beyond belief, remember to disable the CIC too.