TO add a little more information, a Spring Over Axle lift means you move the axle from its stock mounting location on top of hte spring to the underside of the spring, securing it with new hardware or welds and then modifying your steering and brake lines to fit the new height. It seems to add about 4 inches of lift to a Samurai. You cannot SPOA an independant front suspension like the tracker and sidekick, since they dont have a solid front axle.
The general concensus seems to be that its good for off roading because its an easy lift and reduces the amount of hardware under your axle that might rub on rocks or drag in mud. The down side is it reduces on-road driving feel and makes your steering a little bumpy.
My Samurai has a total lift of 6", 4" from SPOA and 2" from longer shackles. My lift was a homemade job done by the previous owner and im not real happy with it so I am replacing it soon with a Rocky Road jp-eater suspension in Spring under Axle, because i do 95% of my driving on road, but i like the look of the 6" lift to much to go back to an unlifted suspension...
Hope that helps.
