Converting a TG16 to a PCEngine

I have a Japanese 3.0 card, but no Japanese system to use it with. I was thinking of converting one of my extra TG-16 units to work with it, and also, all these Japanese cards I have. I've seen smidges and hints about doing it, but nothing absolute. If anyone can point me in some direction or FAQ for it, I would greatly appreciate it. Also, where is a good place to get the tools for opening the system?
Just go her and they have some kind of file on how to modify US system for playing import cards.
Thanks for the link. Some nice info there, just not exactly what I'm looking for. All I could find there was installing some "switch". Couldn't you just switch the wires without all that unecessary "switch" stuff? I don't need it to be able to change from a JAP system back to a US system. I figured I could just hard wire it into a JAP system and leave it that way.