check out this site - they've got the install/removal instructions for all Honda aftermarket parts. You'll probably have to dig around, but I do know I've seen the directions for seat removal. Also, if you search around, there are photos in the electronics/audio section.
Removing the rear seat is pretty straightforward, though you will probably need an assistant to actually pull it out of the truck. (I did it by myself once, but it sure was much easier with a helper.)
1. Pull the plastic panels under the seat bottom straight forward to remove them.
2. Remove the six bolts (14mm) holding the seat and center seatbelt in place.
3. Pop the two small plastic covers at the top and behind the seat using a trim removal tool or screwdriver tip covered in masking tape.
4. Lift the seat straight upward.
When putting the seat back in the bolts need to be installed in a certain sequence. Not sure how critical this is but a Honda engineer told me this and the service manual says the same. Also, the torque specs are different from what the backup camera install docs say and what the service manual says, think I trust the service manual more.
The Service Manual states a 35 ft lb torque and must be re-installed in a certain sequence for the 6 seat anchor bolts (not the seat belt bolts). When putting the rear seat back in install the bolts in this order. (1) center left (2) center right (3) left lower (4) right lower (5) left upper (6) right upper.