It's my understanding that the daystar spacers do not set the ride height on an air suspension truck. If you install only the spacers the computer will deflate the air bags until the normal ride height is obtained. The ride height is set by the air suspension links. If you install shorter links the computer will inflate the bags more, hence lifting the truck. The ride, however will suffer as you're now riding on higher inflated bags. The guys on the Rebel forum are installing both the spacers and the shorter links. The spacers take up the space so that the air bags do not need to overinflate, hence giving you the desired lift with a stock like ride.
I installed only the shorter links to level the front and , thus far, and the truck still seems to ride fairly well. I bought the Daystar spacers as well, but I still haven't decided whether to install them as I haven't noticed the ride changing too much with the links.