The time it takes to complete a body lift depends on how mechanically inclined you are. Also, I did alot of research on XOC...hearing the do's and don't(s). After I recieved the kit, I did some preparation before the day of install. Like spraying all the bolts with WD-40, removing parts that are changed or eliminated with the body lift, pulling back the carpet in areas where I need to access the bolts....things like that. Then when the day came to install, it took myself and Aerosteve about 5 hours to complete the job which included a lunch break and a quick trip to the hardware store. We spent other 30 minutes maybe redrilling and installing the rear bumper....an about another 1 1/2 hours modifying the ARB.
Then I read and hear others that have done the body lift and they take two full days to complete without bumper modifications and breaking parts on their Xterras since they were not prepared or knew what they were doing.
So good luck!