Did you follow the guide on here? Youve probably wired the earth from the head-unit to the illumination wire in the stock loom. Its easy to do as whent he lights are off its an earth, but turn the lights on and its +12v.
As a general rule when installing new electrical accessories into any car i make a new earth, find some solid metal in the dash and attach your earth cable to that.
The dash lights can be fixed by replacing the 5A fuse under the dash, im fairly sure its the fuse all by itself above(?) the row of fuses.