the link below shows a good step by step removal of the DSP amp:
http://www.xoutpost.com/articles/all...02-bmw-x5.html
As KevinKay mentioned, if your replacement amp is from an E53 it shouldn't require any coding and be a plug and play installation. I bought a used DSP amp that was pulled from a 740i and despite being the exact same brand and part number for my X5, it requires coding to operate/sound correctly.