If you don't use your CD player often, this is a great mount.
It's universal but works great with GS3's, easily switches from portrait to landscape, and there are no suction cups and nothing on your windshield.
Ending up having this one http://www.amazon.com/gp/aw/d/B004G1L52Q Recommended on the fiat forums. Loving it.
First off, get this phone mount instead. If you have a phone (which means you have bluetooth and AUX at your disposal), you don't need the CD player. It works wonderfully and makes it feel built-in to the car.
Otherwise, just keep a phone charge cable around.
If you actually want to talk mods, some people have installed backup cameras and integrated radar detectors (that mount to the front of the car), so those would make things better.
This is the best cell phone, electronics holder on the market: http://www.amazon.com/Mountek-nGroove-Universal-Phones-Devices/dp/B004G1L52Q/ref=pd_sim_cps_2?ie=UTF8&refRID=0AH9VQ04RGXAPBM1H9GS
I like the Mountek CD Slot phone holder.
I've used it for a couple of years now, and it hasn't messed up the CD player (I tested it just to make sure, not that I listen to CDs...what am I, your Grandma?).
It fits a Nexus 6 in a case with no problem.
Another option is to get a CD slot mount. Don't have a pic but I just put my phone on that and fire up torquepro.
http://www.amazon.com/Mountek-nGroove-Universal-Phones-Devices/dp/B004G1L52Q This is what I use and its pretty awesome.