Installation is pretty straightforward and no special tools are required. On a scale of one to ten—ten being the most difficult—this job is about a 4.
The pipes are held to the body in only two places, at front and rear by a thin wire clip and/or hose clamp. The 4WD pipes are quite simple to install, being that the gas tank isn't in the way (like it is on 2WD models). Just remove the four hose clamps that hold the hoses onto the pipes, disconnect the hoses, remove the two wire clips and/or hose clamps securing the pipes to the body, and remove the old pipes. Lay out the four new stainless steel pipe pieces next to the old pipes, and it will be very clear which piece goes where. Now just slide in the front pipes first, put back the front clip, join the rear pipe halves to the front halves with new clamps and connection hoses, push the rear half pipes up and into place, install the rear clip and/or hose clamp, install the old hoses with the original clamps—that's it. One tip: Use a little bit of liquid dish soap at all hose-to-pipe connections (NOT grease or oil), and don't tighten any of the hose clamps until all are in place and lightly secured. This will allow you to move the pipes around as needed for best fit.