Another option from the shelves of your local Autozone...
As I was working one night, I started sifting through part numbers of various shocks, looking to replace mine on the cheap when I finally install my SL...
The factory front specs are as follows:
Extended length: 14.95 inches
Collapsed length: 9.67 inches
Stroke length: 5.28 inches
(I have not found the F150 shocks mentioned earlier. Maybe something changed?)
The factory rear specs are as follows:
Extended length: 22.49 inches
Collapsed length: 13.69 inches
Stroke length: 8.80 inches
I am thinking about swapping in a set of Gabriel Hi Jacker air shocks for the rear, since I have the rear tire carrier, and will put my full size spare on it, when I get time...thus it will probably sag more so, and the extra boost the air shocks will provide will help to level things up.
Here are the Hi Jacker specs for the rear. These are actually Chevrolet/GMC K1500 4WD rear shock specs, but will compensate for the lift...
Extended length: 26.33 inches
Collapsed length: 16.35 inches
Stroke length: 9.98 inches
The Chev/GMC shocks are about 25 bucks cheaper than the Nissan replacement, and they sure do look beefier. Had them out of the box and was checking them out, no comparison...especially with a lifetime warranty.