The reason I'm being so obstinate about it is that some Wiis will brick by going anywhere below 3.4. I assume that yours is an older console that isn't affected by this, but still. It's something I don't advise to anyone.
But if you wanna do it, install IOS30 (the lowest version one, not the new brickaholic stub version), then install the System Menu 3.2 of your region. Do it in that order or you're potentially screwed. If you don't have BootMii at boot2, don't come cryin' to me if you screw something up.