They were pretty easy to put on. Should be easy to get off.
IIRC I had to lift the truck and let the rear axle hang loose. Take off the wheels, then bolt on the brackets around the spring pack, lay the coil on top with the "Hook" placed over the end of the spring pack. Then tightened the coils so the "hook" held it all in place. So just try reversing that procedure.
Just not sure that it'll help much though. Suspect your 2500HD spring pack is the problem. Don't suppose the previous owner also added an extra leaf there?