The best way to do this is to remove the OE unit -- and keep it. Just get a unit without all the loud buttons and lights and it will look fine. The OE unit is crap - for lack of a better word.

The dash speakers are quite small -- I can not remember -- They must be 4". I replaced them and I also cut speakers into the flat space behind the seats. 6.5 in my case.

The rear is where all the sound comes from - the fronts are just too small - but they add enough that it is well worth the upgrad.

When you look at the speakers that are in OE systems -- even the very $$ ones -- it is a shock how cheap they are!!

If you do this you can change back to stock with no problem. The rear shelf is just plywood with carpet over it. All the parts are easy to get and the head unit justs pops in and out!

The car is much nicer with a system you can play a CD and hear it too.