Dropping the front won't raise the rear at the rear wheelwell, but it will raise the rear bumper due to the "teeter-totter" affect of the body pivoting at the rear axle.
You can't use lift blocks because the axle tube is below the spring, adding a block will lower it.
Two ways to raise the rear. One is a longer spring shackle set at the rear of the spring, this will raise the rear 1/2 of the amount added to the shackle. Downside of this is a slight decrease in cornering stability, and the fact that if you go very long with the shackles it looks really dorky.
Second way is to take the leaf springs to a spring/suspension/truck shop and have them rearched to make them taller. This is the more correct way to do it.
Don't even consider airshocks, they are a poor way to go for several bad reasons.