Should a W&B list gross weight?

Some work was done on an airplane. The new W&B is of the "removed/added"
sort and computes a new empty weight and moment arm. But the document
doesn't state the gross weight.

The changes were all avionics; no airframe or power plant work was done. So
I'd expect the gross weight to remain unchanged from the prior W&B.

But does the new W&B need to state the gross weight, even if it is
unchanged? If not, do we then need both documents to cover the legalities
of documentation in the airplane?

Or did the person that wrote the new W&B err?

- Andrew