If you can get a complete checklist, please submit it. But this site is very against adding one card at a time. Try to find a complete (or as complete as possible) checklist. If you can't, you're supposed to post a new entry into the forum asking if others can find a complete list. If no one can find any more, they may add a partial list.
I know it's tedious, and I'm sorry, but that's the way they like to do it here. I guess with the way the site is set up, it's more difficult than it should be to add cards to already created insert sets.