Did you manage to take out the shelf under the steering wheel and the cover panel beneath the shelf (or are they what you are referring to as knee bolster)?
There are two rectangular covers on the vertical surface of the tray that you can pry off with a flathead screwdriver. Removing them will reveal screws - but don't unscrew them yet.
Also, under the shelf is a cover panel - if you look up from underneath, there are plastic screws with philips head - note, they are not screws in the truest sense but they are more like snaps - rotate the head, once the pins are aligned with the shape of the hole, then you can disengage the panel.
Go back to the screws revealed after removing the cover plate and unscrew them.
You can now remove the shelf and panel - that should be enough to give you room to work on your CC amp.
If not, then the ribbed black tube that is now revealed that runs across under the steering wheel column (what I refer as the knee bolster) can be removed by unscrewing from underneath using a long shaft screwdriver (sorry, my memory is fuzzy here).
I can't seem to access my gallery to point out the parts at this moment so I hope the text alone is clear enough.
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