Recently I had to remove the seats on my 2004 Commodore SV6 to run 0 gauge wiring to my rear sub. I couldn't find any solid how-to guides online, so thought I would share this information for the rest of the owner's group.
The first step is to push the seats to the back. Since the bolts are on the track, you've got to gain access to them. Pull off the plastic caps and crank out the front bolts using an 18 mm socket. I had to pull mine pretty hard before they would budge, these things are really torqued in there.
Next, push the seats the other way and take out the back bolts (one on each side). Then pull the seats out of the car. If there are wires under the seat, unplug them first to avoid causing damage.
The back seats are easier. You just lay them down like normal and undo the bolts on each side and they just slide out. The top half comes out the same way (2 bolts total).
Do what you have to do, then put it all back together!
Hopefully that help make someone's life a little easier. Any questions can be sent to email@example.com and I'll do my best to throw them up here on the site for the rest of the group to use.