K-Frame ID Needed?

I need help identifying this k-frame. I bought it at the Nats last year and I was told it was a 73-76 SB k-frame but I have been told by a member that it is for a /6 but I am just trying to pin down exactly what year and application for this k-frame.

The second pict is of the back of the k-frame showing the steering box mount and the idler arm mount.

Any help will be appreciated.

Joe

akframe1.jpg

spoolk2.jpg