I have the exact set up you are looking at lift, tires, shocks, everything. I went with 2" bump stop extensions and I ordered everything through Marcus at River City Offroad and he knew the shock length's to order with it. Even with almost 4 inches of actual lift my front shaft has been fine for about 8 months and 15K miles so far.
If you get the RK bump stops you do not need the spring clips. With the shocks fully extended my springs can NOT fall out and the top of them will only unseat by about an inch. I have never had a problem with my springs going anywhere.
You will have plenty of backspacing with the 1.5" spidertrack spacers but you will need to throw a washer on your steering stops to stop that last little bit of rub on the control arms.
Hope this helps. Feel free to shoot me a message if you have any more questions about this specific set up.
2011 JKU Rubicon
PSC Evap Skid
PSC Diff Covers
Dynomax Rock Crawler exhaust
ACE Rear Bumper and Tire Carrier
Rock Krawler 2.5 Flex W/ Bilstein 5100's
35" Nitto Trail Grappler's