Re: Why do Shackles lean out
Do you know if the axles are stock? If both of the shackles are splayed out in opposite directions, the axle spring perches may not be spaced the same as the top of the shackles. Check this.
Lift it by the frame and see what happens when the load is off the springs. Do it slowly so you can see what moves and isolate the problem.
Only after you find the problem should you try to fix it.