My 03 has what amounts to a 2/4 drop. I chose the Belltech drop leafs because they have a higher spring rate than the stock leafs and are more than adequate for towing.
Belltech 1-2" PRO Coil Spring Set, P/N BEL23804, ...............$ 123.54
Belltech Shock Extensions, P/N BEL6657, $55.99 + 10.99=.. $ 66.98
Belltech 3"-4" Rear Drop Leaf Springs , P/N 5986, $ 120.13 X 2... ...$ 240.26
TOTAL: .................................................. ..........................$ 430.78
Sulastic Rubber Springs (too reduce bed bounce & harshness)$ 269.00
GRAND TOTAL............................................. ......................$ 699.78
Running 22" wheels w/285/35's Front & 305/40's Rear.