Thanks for the info. I checked the fuse first (and to be honest, what I hoped the problem was, a fuse is easy to fix), and couldn't find any duff ones. I had a look under the steering cowls when i took the speedo out to investigate it's "waaaay offness", and I couldn't tell 100%, but it looked wired up, but I'm no auto electrician.

I took the car down to an Audi garage to investigate the whining, which they reckon is the diff, so I asked about the ABS and the Cruise Control, they say it might be related, but he thought the electrics for the ABS were all fine.

The clutch and break pedal switches make sense. I will check when I get a chance. Just a couple of questions, where are the switches going to be, are they going to be way up there, or not too far north of the pedal itself?
Second, assuming it's the pipe, where is best to look? Will the pipe just run near the injection system, or is it going to be a further run?

Thanks again for the help! :-D