Thanks for the links. Cats to cats I'm really familiar with but I will check out both.Most of the articles are written from the standpoint of the dogs being older, not the cats, but here is one method that works. In the articles section, there is one about introducing cats to dogs. (I tried to link it, but my computer is not cooperating. The next link works and is in the same section.) I am also going to include one for cats to cats. www.thecatsite.com/a/introducing-cats-to-cats
Using a combination of the two, you should get some good ideas. The biggest thing is to do it slowly. The cats will see the dog as an intruder on their safe and comfortable home, and the puppy will see two tigers that want to eat him. Being a puppy and wanting to play with anything and everything will make it a little harder.
Take it slow, and keep asking questions and giving updates.