New Front factory springs

[RCushing]

A while back my truck was hit in the left front. After the repairs, 2 new factory springs and shackles, upper ball joints, and many other items, the steering center was way off. I installed a new drag link and both tie rod ends. Brought truck back for a new steering box and an alignment. All being paid by insurance. After all this the steering is still way off center. Today it was put on frame rack and all measurements are good. What they did find on the new factory springs was the measurement from the eye at spring front to center pin on spring was 1/2 different from one spring to the other. Part number on springs are the same, and springs are not reversible. Does anyone know if they are supposed to be different? Should one side be longer than the other?