I was wondering about that. what about using Scorpio springs? I believe they are longer. I never really checked them against stock sierra springs but they were def. loger than the ones I had. Scorps would have a stiffer spring rate also. I choped a coil from the set I put on my sierra and it rides well. In your case might be better to cut the top coil that is smaller (softer) taht way it utilizeze all the spring.if not maybe just put it in the car as is?..

just an idea!

i will see what i can find also while I am at the J-yard.

later,
TF