not a serious answer but
my good lady wife found out the best way to remove the stereo in my 200SX Turbo. She waited until we were on a dual carriadge way, about to come into a roundabout, then at 5,000rpm decided to floor the go pedal instead of the stop pedal. Imagine the surprise on my daughters face from her kiddy seat as the stereo shot from the dashboard past her right ear and ended up on the parcel shelf once we had stopped using the previously untried method of the back end of a Pug 309!
Your best bet though is to go to Fiats, bung the geezer a fiver and ask him to pop the stereo out, it is much better than buggering around yourself and knackering the dash.