what you are wanting is for it to square up better. I doubt it will be a simple righten the diff issue. I was having the same thing a couple weeks ago. I switched from the 1.7 to the 1.6 pistons and went back to the c hub with no washers. Since I did both changes at once, not really sure which change foxed it, probably the c hubs. You may be diffing out. You might be able to help it with tightening the diff slightly. Like most things there are a few ways to fix it. Soften the rear springs, c hubs, heavier pack, maybe tighten the diff a little, stiffen the front, change tires, etc. for me the c hubs seemed to work and I back mounted them, so no more spring rubbing.