I have the CST 4" spindles on the front with and additional 1" spacer on top of that (5" total front lift). The stock shocks will be fine to use with the spindles. Just my .02, but if you wanted to save some money and wait to get the shocks that you want, the stocks will work just fine.
I had a 2.5" lift spacer on the front before going to the CST kit, and the shocks were pretty much topped out. The CST kit feels MUCH better and smoother than when I had the 2.5" spacer on there. From my experience, It would be safe to run up to 6" total (CST plus 2" spacer) before NEEDING to get shocks. You also dont want to get shocks that are too long, then your opening a whole new can of worms when the suspension components start contacting each other! (that is what I have read, and been told numerous times)
09CC4x2 CST 4+1 Front, 20x9 Fuel Nutz 295/60 Grapps, Black Heads+Tails, CAI, Predator, Custom Exhst