Welcome to 4x4Wire. Ditto to what Russel noted. The more information provided, the more you will receive answers that apply.

Bilstien and Fox are both quality shocks for your application.

I am not a fan of blocks for suspension lifts. I have had success with coil and strut spacers.

Springs -- you are right to ask questions. There are a lot of trial and error setups that lead to problems. There are two spring companies I encourage you to check.

Dever Spring and National Spring. A Google search will turn up their web sites.

Both companies make custom springs for desert race applications.

For complete kits, RCD, Rancho, and Rough Country make quality products.

Year of truck is important as factory design will limit some choices.

You note you have about a 6" lift. Personally, I believe that is excessive and limits performance. You need about 2.5 inch lift to accommodate larger tires. Going more than 4" of lift introduces stability issues. And, when you add larger tires, you get into the point of needing to re-gear.