sorry I mean to give you your alternate option also, sorry doing the lone ranger deal lately and don't have a ton of time, ususally calling or emailing gets things compelted easier till I get more help hired
but if you want the lesser expensive deal you can do this
remove the rear leaf springs, remove the overload spring from the pack
reinstall leafs with the shackles, this will set you pert near level, and give you a killer lowered look without changing the ride
now with this said, and again I emphasis the 500hp, you really need to install caltrac traction bars or a long bar kit, both can be had for $500 or less, caltracs are seriously my choice but both will work
the problem is removing the rear overload will weaken the rear spring pack , and under acceleration the rear axle will twist, thus causing wheel hop, vibrations, or worse. so some sort of traction control to keep the rear axle steady is a must, or you will hate it later.
as said above , you can call or email, be glad to speak with ya and work you thru it, I just don't have much forum time anymore.
but that should give you the look you want , the ride you want , for the $ you are looking at.
oh and thanks for the up an up, much appreciated, hope I helped him some
rockin