Did you use a 1" relocation kit in the hanger and the shackle or just the shackle? You need both for full benefit.
Also, if you use both ends of the 1" kit, do you know that the springs in an E body are splayed? They are not parallel to the frame or the center line of the car, but rather are narrower at the front. This means you will have more tire space to the front segment than the rear segment. You would need to relocate the shackle another 2" to make them parallel.
3/4" shift in the housing isn't a lot. Inspect the front eye bushing to see if it is centered or offset. You could try pressing the front bushings to one side to gain .25-.5 of an inch, depending on where you are starting now.
