[special-K]

I`m not sure how the factory determined spring rates,but on a 1/2 or 3/4 you could have HD springs.Maybe an extra leaf,different taper,thicker,more tempering?I know you don`t want to kill your ride.I had the leafs on my`90 Blazer arched and they added a leaf to hold it.It rides nice.It`s a little different than Add-A-Leafs that are an overarched leaf you squeeze in there to "force" the other leafs to arch.When arching springs,the metal is actually "stretched" and this serves to soften a spring,that`s why they add another leaf(which is arched to a matched contour).I arched my own lift into some springs using an anvil.That`s stretching the metal.Start in the center and draw it out from there.I didn`t add a leaf.The truck never sagged while I had it and rode fine as stock.The 1/2t leafs may have a softer ride,can`t say for sure.But,what you`re considering is the best way to get a couple inches,not stiffen the ride excessively,short of buying soft design 2" lift springs.