License Requirements
A Shellfish/Seaweed License is required for harvesting razor clams and must be in the harvester's immediate possession and available for inspection during harvest and transport. Everyone claiming a limit must actively participate in the harvesting process, unless they possess a disability permit.
Clam guns or shovel works, I have dug them by hand not the easiest way to go.
Remember to keep your clams in seperate containers for each person digging.
You do not need a shellfish/seaweed license IF you have a combination fishing license! I made the mistake of buying my clam license for years before I figured out you don't need it if you have your combo fish. Nice job on those clams, the broken one's must be on the bottom 
You are correct,
From WDFW
A shellfish license is required to take anything classified under state shellfish regulations, including sea cucumbers, seaweed, and even squid.
The combo License you are talking about says.
Annual Combo Fishing/Shellfish
It includes Shellfish
