Well I'm not sure exactly what you are seeing as the overlap in the claims you posted. I'm not sure if it is that important to try to sort it out either. However I will do this much. Look at the title of the two patents in question.

584. High performance, low cost micriprocessor using instrustions that operate within instruction groups.

749. High performance, low cost microprocessor with combination stack and register architecture.

As I previously stated. The 584 is drawn to how instructions operate. The 749 is drawn to an architecture for implementing the 584.

But you may have the last word if you wish.

Opty