Super Stock leaf springs

Are the rear shackle brackets bolted on (OEM) or welded in? It kinda looks like the rear brackets are too far back, as if the OEM boxed area was cut out.

In my OEM application, I installed 3/4" spacers to move the shackle brackets forward so the top pivot was in front of the bottom (leaf spring rear eye) pivot.

View attachment 1716157602
This ^^^^^