Replacing Shocks on 2002 Lincoln Navigator

I am considering replacing the shocks on my Navigator. Is there any thing I should be concerned with.

2 answers 2 comments
The front are straight forward tube type shocks that go through the front suspension coil springs, little disassemble is required that involves anything but the shocks themselves, about 1 hour work for both sides, rear are also tube style shocks and go from the rear axle to the chassis, very simple to install, (under an hour both sides rear).
I believe you have air shocks in the rear. If they are not leaking, don't replace them.
You have air springs in the rear. Unless you are having a problem with you rear load leveling Don't touch the rear.
I WANT TO CHANGE MY AIR RIDE TO SHOCKS BECAME THEY ARE DOWN.