Wow, I would give you just the opposite advice. Unlike Sac State, I installed my leveling lift myself on my XREAS equipped 4Runner. Unfortunately, the hoses for the XREAS system make it impossible to remove the strut assembly from the vehicle, instead forcing you to work with the hose still attached. This is an awkard position to work, especially when removing or reinstalling the top of the strut into the strut towers. Its also much more difficult to work with spring compressors when you are not able to pull the struts off the truck.
If you decide to do the work yourself, I would caution you to avoid putting a lot of stress on the rubber hoses. You may not cause a leak right away, but stressing the connections too much can definitely lead to premature leaks down the road. If you do th work yourself, you will see just how difficult it can be to work with the strut assembly with the XREAS still connected.
If you decide to get the work done at a shop, make sure they will assume full responsibility for replacing the XREAS system if they should cause it to leak. You might have a problem getting a shop to accept that responsibility though. Im not trying to scare you or anything, but rather just expressing my opinion that it is not difficult to do damage to the system while installing the spacer kit.
Good luck. Let me know if you need any assistance.