If you don't want to run cables to the boot, then you're generally limited to under the front seats or in the dash. In-dash would require a small amp - if it is at all possible, which is far from certain. Glove box might be a possibilty...

I'd expect the Seat (as it's a part of the VAG group) to have the same standard issues as the VW and Audis - switched pin 4 & 7 in the ISO power/signals connector and probably an amplified antenna which requires an adapter so it can be fed power.

You say you got no sound - did you verify the power and ground? Did you check that you got +12V on the remote power on line from the empeg when the empeg was on? Did you verify you speaker connections?

Also, check out the Installation part of the FAQ (linked at the top left of any page of this BBS), and the sites listed within it.

/Michael