The fact that you have two small groups to integrate definitely works to your advantage. It's much easier to mingle groups than it is to add a single bird to an existing flock. I introduced two groups of three, last fall. They each had a small run/coop setup where there was a common wall. You should have seen the posturing they did through the wire. You would have thought they were out to really clobber each other!
I kept the two trios in their own sections for a good month and a half before taking out the removable panel between them. By then, the posturing was pretty much over except for a bit of name-calling through the wire - much like little boys sticking their tongues out at each other, just because they could.
Once the panel came down, it didn't take long for the exploring to start. There was some squabbling while they figured out their new pecking order, but all in all, things went pretty smoothly. I left the dual water and feeding stations up for awhile, at least until they were all sharing the larger ones. They've been contentedly co-habitating all winter, now. So far, so good.
I have to say that I am pleasantly surprised at how bloodlessly the integration went. Each group still roosts together, but separately from the other trio. They mingle, eat and drink all day, together. The only issue they have is not one at all, according to them. When one crows, they ALL crow. It's a regular chorus for about twenty minutes, at least a dozen times a day ... starting at 4:30 am. I am SO grateful for tolerant neighbors!
THAT'S IT! 
I was looking in articles and thread titles. I didn't realize that it was buried in another thread ... and I even scanned the beginnings of that one! Thank you, THANK you, THANK YOU!!!!!
