If you can unbolt the bottom now and let the shock extend all the way and see how much travel it has in it. Kind of go from there. Worst case the ride will suck a little and the shocks will get damaged...then get longer shocks. Shocks are tough, I learned with trial and error on my truck. My sits taller than most 6" lifts so finding shocks was a bit of a pain in the ass. I bought a set for the rear that were way short but for a 6" lift. Now the ones I have are way long but do the trick. my fronts were easy since I have the hoops. I measured from mount to mount at ride height , on a jack and went from there nowing close to how much travel I needed.