The number of Titan parts that you can fit on a Frontier is pretty amazing, although I think that is a part-time 4wd as well.
I'm not sure the Armada or even the Patrol come with parts for full-time 4wd, but the Rouge, Murano & GTR come in AWD, maybe that's the source of your parts?
As a word of caution, there has been a bunch of effort figuring out how to disable or circumvent the various traction/stopping aids when driving Frontiers offroad (ABS kicks in at 3-4 mph, for example).
Even with a compatible mechanical system, the computers in Nissans are not easy to work with or around--they could be the undoing of a major mechanical victory.
All that said, the 4wd system in the Frontier is pretty bulletproof. If the wife is not inclined to turn the knob from 2wd to 4wd, which can happen up to 55mph if you're pointed straight, leave it in 4wd the whole time.
The turning radius will get even bigger and you may have to replace the tires more frequently, but the driveline will happily take it, on-road or off-- Full time just means never putting it in 2wd.