Found the pics
Here's how I went about it:
1. Undo 2 screws under the steering wheel. The column covers will then pop off (with some work). One will move up, the other down as shown here.
2. Remove the stalk so you can work with it easily. I don't recall having to disconnect anything at this stage - I think.
3. This is the box you'll find inside. You'll need to unclip it in a couple of places to open the box up. It's pretty easy to find the clips. I may have just used a screwdriver to prod where necessary. Be sure not to lose that spring you see towards the right.
4. Once open, you'll find the circuit board. At this stage, if you play around with the lever, you'll see that horizontal arm move back and forth. As it does, it causes two rollers (underneath the white block towards above the goldish strip) to roll over a contact point. This is how the mechanism works - rolls over the strip to trigger the switch.
5. Carefully remove the little white box. It's tricky at first as you'll need to ensure you don't break / lose anything, but it does come out pretty easily if you're careful. It's pretty much just a matter of moving the horizontal arm out of the way and taking the white box out.
Once you've got it out, you'll see the rollers. The reason the circuit becomes dodgy is that the rollers collect dirt / glaze over after a while (as you can see in the pic). Sand them down lightly to expose their regular gold surface - I don't have a pic of them clean, but you'll know. Reverse order to fit.
Been a good few months since doing mine and they're still working like new
Hope that helps. Seems like more of a mission than it is really. The job can take less than 45 minutes if you know what you're aiming for.
I chose to repair mine as parts are hard (and costly) to come by in South Africa. If you can find a cheap replacement, it's probably worth just buying.
Edit: For some reason photobucket thinks my last two pictures should be in a portrait format, no idea why. So for point 4. Horizontail arm is now vertical arm.
Edit again: Seems to have made them landscape again. All is well.