Do you mean torque box reinforcements or new torque boxes? If you need new torque boxes...you're in for a treat! You're going to have to remove the rear seats and carpet, rear axle and control arms, and the fuel lines as well. Best thing to have would probably be an assortment of powerful air chisels with different angles to break off the spot welds of the existing boxes.
For reinforcements, I would buy some battle boxes and follow the directions. The lowers are pretty simple and do not require control arm or axle removal. The uppers are much more involved. I just did mine about a month ago.