I did some spring work today also.    I decided to change out the lower leaf and add a longer add-a-leaf to the spring pack. It seems the spring pack had too large of a "gap" in the leaf length progression (between 3rd and 4th leaves) and caused some undesireable and unwanted handling characteristics.  On the road it would feel as if it would "bobble" from side to side after hitting certain bumps and it was a little scary sometimes  . BTW, this was not a DW since the steering wheel didn't shake at all.  It steers fine.  

1)   Before longer AAL  (see leaves 3 and 4)

2)   After longer AAL

I took it for a ride and it was much better.    It still "bobbled" a little but not nearly as bad and was definitely more predictable.