It's also usually necessary to install an adjustable track bar in the rear to re-center the wheels. It's also necessary to relocate shocks in the rear if you go lower than 5 inches. After 5 inches, the shocks are at such an angle that they really can't work as they were intended anymore.
And NEVER cut springs, Drop springs are just too cheap to risk messing with springs that are probably 30 years old and barley doing what they were designed to do.
The springs' main function is to keep the tires planted on the road so that you can maintain control under normal AND non-normal driving situations. Cutting the springs on a truck that is driven daily compromises the ability of the spring to keep the tires planted.
At around $100 for drop springs, it's just too cheap to not do correctly.
Dval