How does the actual space available for passenger accommodation compare between 747SP and 777-200?

747SP is slightly wider (cabin width 610 cm on any 747, 590 cm on 777) and has upper deck. But its length is 56,3 m, compared to 777-200 63,7 m.

Maximum no-frills seating is 440 on both. But this is exit limited in both cases. How would the non-exit-limited passenger accommodations, at equal level of comfort, compare?