Finn,
Since you say it's urgent, I'll pipe up although I am only a beginner. To remove the steering pad and so gain access to the nut that holds on the steering wheel, just pull the pad around the edges. It will just snap off. However, all you'll see is a largish nut that holds on the wheel. I very much doubt this is the cause of your problem.
There are 2 bushes at the bottom of the column before it enters the steering box, but in my case a problem with these demonstrated itself by excessive play in the steering. Replacing the bushes cured it. There was no creaking noise, though.
I assume your car has power steering. Along Douglas' line, is the steering linkage properly lubricated? Are the bushes in reasonable condition?
JH