XHD rear Leaf spring question P4452982/3

Those are B-body springs. They might be too long. Also they take a larger size bushing than A bodies. If you can even use them due to the length you’ll need b-body bushings and then a sleeve to run small diameter bolts for the A body hangers/shackles

Which province are you in ?
You are right! Even though the catalog says they are same for A" body cars they are too long. I have ordered P4120863/P4120864