They may break on you no matter what (3/4 mine did). If they do, it's no big deal if you're willing to cut a few 2"x3" (roughly) holes in the cab.
I used an air-chisel to get off the weld-nuts, then used my old rear sway bar mounts to make BPE's and attached the whole deal to the old holes with grade 8 hardware and lockwashers.
There's a hole in the center of the underside mounts, I drilled through it into the cab to locate things for me then went into the cab and used an angle grinder to cut my holes. When the everything was together I sprayed rust-preventive primer all down into the holes and all over everything inside the rails (that I could reach). I cut a couple of pieces of flashing to the right size and sealed them down over the holes with a fat bead of RTV to keep water and dirt from coming back into the cab.
If you're set on doing it in one day, be prepared for this to happen.
Also be prepared for the bolt in the front eye of your leaf springs to be seized in the metal sleeve inside the eye bushing. On mine, one side came right out, the other side bound up. I still managed to get the AAL in both sides, but I did the side that was bound up first. In worst case scenarios, the weld nut will snap off inside the frame, to fix that one I've heard of people cutting or drilling access holes....
A 2" lift should slide right in, to fit 3.5 I had to have my front sway bar off, and of course I snapped the torx bit that I had trying to get the links off. I ended up just hacking the links off and pulled the bar.
Get a hold of a coil spring compressor, external type. You probably won't need it for a lift of that size, but if you need it, you'll NEED it. One of my bumpstops wouldn't come out and the compressor made a 5 min job of switching springs and kept me from destroying the bumpstop to get it off.
Air tools, cutting equipment (angle grinder & torch), and being prepared for the worst to happen will go a lot of the way towards having your lift done in one day.
