I've lowered mine with a 2" drop bracket in front and 3" springs and hardware kit in the back.
What I've learned: (mines a 2003 cladded for reference)
1. Do not use torsion keys, they will destroy the ride quality.
2. Drop brackets will make it where you need to cut the end of the upper ball joint. 17" rims will not fit anymore.
2. If you're lowering the back, also put in the 'hardware kit' from DJM. Ride quality, bottoming out, ect. HUGE difference.
3. Shock relocation brackets will work, but I wouldn't depend on them long term. Replace the shocks with recommended shocks.
4. Be prepared to spend more than you planned on replacing other parts. Unless you're not like me and can put worn out/damaged parts back on the truck. I spent extra $$ on lower ball joint, inner and outer tie rods, front sway bar links, cv axle, wheel bearings, rear sway bar hardware, shocks on all 4, rims and tires.
5. Depending on different things, each install is different and unique. Not having the right tools will cost you trips to the store, or headache trying to get it right.