Sandblasting is the obvious way to get down to bare metal, but I would not suggest the powdercoat especially if you ever plan on doing any modifications to the truck that would have you grinding or cutting on the frame. Modifying mine for bags, c-notch, shock relocators, and such has required the removal of at least 20 frame rivets and frame cutting. Course if you wait to powder coat after you have done all your mods, then more power to you, but who knows when the mods are done...