E53 X5 2003 Amplifier Question
 

There is no sound coming from the stereo but the head unit is powered and displays time/stations/etc. Also the CD player works but no sound. It has DSP but no NAV.
I've read alot of threads on site but haven't gotten a clear answer.
I've disconnected the battery for 1/2 hour and reconnected but didn't fix issue. (read this on one of the threads)
I bought a used amplifier (same part #) on ebay for 200.00 (hopefully it's functional it was listed as tested and functional) and I am going to swap out bad with good but was wondering if this is an easy task or is it difficult. Looks like there are 3 connectors on top and 2 bolts at top/side that I have to remove to slide it out.
Also how difficult is it to remove the plugs?
The amp is a Lear 65.12-6 905 119.
BMW info: X5 E53 3.0i 2003
Also does it need to be coded?

Any help would be appreciated.