Lowering rear of car

I have super stock springs on my Duster. They make the back of the car sit really high. When I installed the relocation kit I drilled extra holes on the front mounts about 3 inches higher than the pre drilled holes. I tried changing the spring to the top holes and it made the driveshaft bind up. The car would only roll 5-6 feet then stop. I guess it changed the pinion angle. Someone told me they had heard about putting blocks under the springs to lower the body and it wouldn't affect the pinion angle. Has anyone ever done this? Where do you get the blocks and wouldn't you need longer u-bolts?
Thanks, Tom
Author: admin