Another engineer here . The harder you make the strut rod bushing is not better. The bushing is suppose to allow the control arm to move up and down freely but not front or back. If not the strut rod will break as the problem they had with the early a-body cars. That is why they went to a thicker bushing in later years. Did you also know that you should never tighten any bolts that secure any busings until the car is at ride hieght getting aligned. If you do you will rip the bushings and they will be permantly destroyed. Upper and lower control arm bushings with inner and outer attached sleeve are made to travel the same distance in either dirrection. If you tighten them when the car is raised and then bring it to ride hieght you already put it at half its travel. As soon as the car dips when driven the sleeves will rip from the poly or rubber, This is not the case with lower poly because you leave the original sleeves in place and lube the bushing. But all uppers and OEM lowers this mus be done.