Not to hijack this thread, but I'm in a similar predicament, though in my case it's that I can't stand the western layout and prefer the Japanese one.

With that in mind, is there some sort of dongle or something that a Dualshock 2 can plug in to that lets you remap buttons before the signal reaches the PS2, kind of like those devices XCM makes for Xbox 360 controllers?

It's the only way I can imagine this could be done considering something like Macrofire (PSP remapping plugin) is likely impossible to create for the PS2.