[SkidmoreGarage]

I'll weigh in first, I guess. I won't pretend to have the answer, my new suspension is untested as of yet. But the fundamentals of my suggestions are sound, so I'll proceed. I haven't measured it myself, but I've read that 5" rear drop gives you around 3.5" between the axle and frame. This is the same whether it's lowering springs, coilovers, and/or lowering blocks.

Traction and comfort are surprisingly similar goals. In both cases you want to keep the wheels controlled and in contact with the road. Unfortunately, payload capacity and comfort are opposing goals. To be able to control a heavy load, you need to be able to resist forces that are in addition to that which the truck normally sees. So for comfort, you want low spring rates (but correct for a 4k lbs truck) and matching shock valving. If the struts are valved for HD load they will resist the impulse to move, which leads to a jarring ride. If the springs are too stiff, you will also experience that it takes a lot of force to move the suspension, and you will feel that as harshness.

To stop the axle from hitting the frame, you will want to utilize modern bumpstops. This will add a progressive ramp rate to the spring when you reach the end of travel.

The third part is that you want to maximize suspension travel. This is why most people recommend drop spindles and lowering blocks to start. These allow for standard length springs and struts. You won't reach a 5" drop with drop blocks, but you may be able to use a 3" spring and 2" blocks.

The final part is, what is best coilovers or regular springs and coils? The answer is that they are the same. Coilovers just move the spring to the strut, and have an adjustable spring platform. However, when you do this, you will increase the demand on the shock mounts. This is why you see aftermarket companies creat mounting kits.

With this info, hopefully you or someone else will be able to ask the right questions when shopping around. If I had to make a suggestion for you:

Front: 73-87 stock arms, sway bar, and disc brakes, 3" drop spindles, new stock springs or stock height but lower spring rate. Use a high quality OE style replacement shock, can be same brand as rear for bonus points.

Rear: 2" drop blocks, 3" drop springs with the softer 200-225lb rate. The NLE shock relocation kit and the longer shocks they recommend. Replace stock rubber bumpstops with bolt on belltech or energy suspension bumpstops.