Did you do the install, or did you take it to someone? Sometimes on higher end radios "good" shops run that wire straight to the battery (to avoid engine noise, and for a direct contact). If thats the case there may be a fused link close to the car battery.

Unfortunately, that wouldnt explain the clock going out. Im willing to bet the clock fuse is tied in with several interior components (i.e. dimmer switch). Your best bet is to get a multi-meter/test light and check all the fuses in the car & under the hood (if you use a test light, be carefull with abs/cruise/airbag fuses).

If you dont have the tools, but have some spare time...try pulling each fuse individually and visually inspect them. MAKE SURE THE KEY IS OUT OF THE IGNITION! Good luck...