Months later I can say that the method of keeping all cats confined together in one room worked well. We used the feliway plug-in and the Bach's essences in their water (can't remember which one).The three of them lived in the guest room for 6 weeks! We were having work done on the house and people in and out. They seemed very content in there, resting together on the bed and NOT fighting. We would let them out one by one or together in the evenings and they generally get on much better now.
Our outdoor cat lived in a homemade fenced-in run that we attached to his cat house under a shade tree. Also for 6 weeks. He got fat in there! He actually preferred to "coop up" at night in his new digs for several more weeks. Eventually he abandoned the contraption altogether and we moved his house under the carport. He's also well adjusted to the new place and much happier then the other house.
Thanks for the advice. We've also changed all the boxes to the rubbermaid bin you describe elsewhere on this site. It's perfect and they like the precious cat litter too! I'm glad we made the efforts. Our family is much happier these days.
Here's a video of Jakey Pete relaxing in his own way. http://www.youtube.com/watch?v=2xnAhVYGyJE
Thanks again, Amber
RESPONSE:
Soooo glad to hear things have worked out! Having a happy cat family makes all the effort worthwhile! Enjoy them!