4x4 axle alighnment

[Tony]

My 68 K10 short bed drifts to the right ....The front end alignment is as it should be, all the parts are in good shape.
I'm putting in new bed wood any while the bed floor is out I measured the rear axle location off the spring hangers it was off nearly a half inch. After loosening the u bolts it was obvious they were loose in the past and the center bolt fretted out the locating hole. So the axle is now where it belongs.
I moved to the front, same thing the front axle was off about the same in a direction that would cause a drift to the right.
While measuring off the front spring hanger I see the center bolts vary by half an inch on left and right sides. The springs appear to be original unique type taper two leaf type...The spring bushings aren't distorted or broken...
Using the rear axle as a reference I enlarged the axle center bolt holes and shifted the front axle into position...
The frame has a two decent looking crack repairs done in the past but shows no accident damage.
Measuring diagonal across the frame in several places shows it's not jacked out of shape....
On the front springs, they are identical left and right, yes?