Hotchkis leaf springs on a'63?

Lefty71 said
Learning moment maybe?? If these work for cars previous to '67, then why would they not list them for the earlier cars?? Just curious.View attachment 1716477986

The springs are the same from 63-76. Might be for 60-76, I'm not sure. Course the 62 Dart may be an exception, since it's a B body.