Just to save you some time and effort, swapping the springs from side to side won't cure the lean. Many have tried this and stared in wonderment after going to all the effort to no effect.....
Many times, not even new springs fixes the lean as the car has taken a "set",
BUT........ ..
look at the car from the passenger side. Look especially at the front and compare it to the driver's side. If you see that the right front is higher than the left front, then go the back of the car and lift the driver's side. See how it goes down on the passenger side front?... The trick is to lower the passenger side front, which will level out the driver side rear!... get some spacers--- I used 3/8" washers, each 1/8" thick, and put them under the right side front spring pan, installing longer bolts as needed. ... VOILA!
This fix also helps the steering geometry, odd as it may seem.