I didn't spend near that much to drop my blue '66 C10, maybe only $800 bucks. I did it in two stages- the free way, I cut 1.5 coils off and removed the bump stop bracket to gain more travel. I also relocated the shock mount further up the frame to keep use of the stock length shocks. On the rear I removed the bump stop brackets and bolted in leftover springs from a friend's Jeep TJ for a 3-4" drop. I wouldn't go any lower than this up front with just cut or drop springs, you get into geometry/travel problems and the springs get loose in the cups when you lift the truck with a jack.
Stock height, and cut/jeep springs. The jeep springs are too soft if you plan on hauling or towing anything.
When I wanted to go lower I used CPP's disc/spindle kit, added rear drop blocks, a mild pipe notch, stiffer drop springs, and relocated the rear shocks using FrizzleFry's method. I left the factory single circuit manual master cylinder in place with no issues. The pedal feel and effort were really good actually, I never wished I had a booster. This is as low as you can go up front and have decent ground clearance, inner fender clearance, and suspension travel. Any lower and you'll need to section the crossmember and clearance the inner fenders for more up travel.
I modified a set of rear axle shock mounts so they'd bolt to the frame rails up front.
FrizzleFry's cheap/super effective rear shock relocation method, post #11. This works better than the normal relocation kits since it gets the shocks outside of the frame and closer to the wheel so the shocks can be more effective. I used gas shocks all around and sway bars front and rear and it drove great and cornered with less body roll than my autocross car.
http://67-72chevytrucks.com/vboard/s...postid=4730005
