Hi Starky, on nightshift so sorry for the late response, Wul has covered everything for you
If you are worried at all about the cable running under the sills (easiest option) you can always remove the seats and run the cable under the carpet, follow the other cables there and tie wrap the changer cable to those wires which should eliminate any rattling :evil:
Things to note there:-
1) Do not turn on the ignition with the seat air bag disconnected from the seat or you'll have to go to the dealer to get it reset :evil:
2) Before you tie wrap the cables make sure there is no distortion or engine whine, oh and did i mention, don't turn the ignition on with the seat disconnected
I'm sure you could get the changer in the glove box, but, you'll have to remove it first and get access from the outside, just make sure the magazine can be removed :clown: