It really is worthwhile to search Itallan sites when looking for stuff like this.

The Alfa 147 Virtual Club has an interesting Hi-Fi and Car Audio forum. There's a topic about the Blaupunkt double DIN adapter for the 147; probably just what you were looking for. It should allow you to mount your empeg underneath the factory radio, sacrificing only the cupholders. Now this is all assuming the 147 console is shaped exactly like the GT console...

Pim