Heres what I did today - using all old parts I had laying around the garage, including the grey carpet, woofer and port (made of 60mm PVC)
Pioneer 480W 4ch amp running front stock splits and 12" JVC free air woofer, with my ANS-810 headunit running aftermarket rear door speakers (none stock).



... please excuse the giant mess of wires
when I ran all the cabling I wanted to be sure I had enough - running all of the cabling in the octavia wasnt that bad a job but I dont want to do it again 
**edit (photobucket seems to be down or something atm, pics may come up later, sorry)
Pioneer 480W 4ch amp running front stock splits and 12" JVC free air woofer, with my ANS-810 headunit running aftermarket rear door speakers (none stock).



... please excuse the giant mess of wires


**edit (photobucket seems to be down or something atm, pics may come up later, sorry)