Right! I made some success, but the left side of the stereo just - will not - budge!
@pubsinger: youre advice is sound, thanks. I managed to get the trays out but even with my hand under and beneath the stereo unit, I could for the life of my not pull it out.
In any case, I think I managed to connect the USB-adapter. From what I could feel (and later google), there is only one real place where the socket connector can go. Took me a good few tries, but I managed to push it in there. For some reason, the stereo won't recognize the device as a CD-changer (i.e. it doesnt recognize it at all), but I guess thats for another thread.
Again, much obliged for the help, lads!