cat integration

It's been a while since I've posted anything.  I adopted a new cat Shadow, brought him home from the vet on 10/31 to my house which contains one very spoiled princess Sugar Bear.  Shadow is about 10 months to a year and Sugar Bear is 5.  I had done a lot of research prior to doing this, it is a huge commitment as I work 12 hour night shifts.  He was starving and alone outside so I felt I had to.  After about 4 weeks of no progress I had decided I had to find him a new home as I didn't feel I had the time to put into making this successful.  As you all know, it's so hard to find new homes for kitties so we'd been living with them separated since.  I finally decided to try again.  Going through the steps again.  This time a suggestion was given to put the new kitty in a kennel and let the resident cat out.  We've done that three times now.  It's going ok.  Shadow just kind of sits there pretty wide eyed.  Did a lot of staring at SUgar Bear but no hissing, or growling.  Sugar Bear on the other hand is VERY hissy and very growly.  More growly.  NOrmal?  I think it is.  And she does finally settle and will lay down but for the most part continues to growl.  Feeling very discouraged when I read the stories of the quick easy integrations because this is exhausting.  Any insight?

Yes, Sugar Bear's reaction is quite normal.   Here's a link you may want to read. http://www.thecatsite.com/a/introducing-cats-to-cats