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Search around and you'll see lots of threads on this, but the best way is with 3" lowering I-beams from DJM or AIM. They usually run around $500-600.
You can also cut the stock springs or get 2" lowering springs then have the beams bent to correct the negative camber that the springs create.
The rear is the easy part, you can get either spring and hanger set or a flip kit to put the axle on top of the leaf springs depending on how much you want to lower the rear.