I ordered mine from xterraperformance.com because it was on sale (same company as nissteclifts.com). I would post a direct link, but I apparently haven't posted enough yet to do so.
Part Number: N-17TI-TOP2-UCA
You can select what size rear block you want. I also needed the camber bolts. I talked with one of the guys at Nisstec before I ordered it. He was extremely helpful. He said that some of the Titans actually have the camber bolts from the factory. So you may want to check yours first.
I got this kit so I could maintain the factory ride. I did a spacer for my '13 Pro 4X and it stiffened up the front suspension too much for me.
The measurement from ground to center of wheel well after lift:
Front 39" - Rear 39.5" (with my tools in the bed)