When we have introduced new birds we have always done it at night and put them into the house. The first morning can be rather traumatic but try and let them get on, uninterupted, with the pecking order disagreement. Any interference can only prolong the fighting. Some birds are ok and submit straight away whilst others go at it hammer and tongs until the new hierarchy is established. If you have the space and a moveable run you could move the run in the evening when the "old birds" are inside, then introduce the new ones. In the morning neither group will know who is the new one as the area is different to both! There will however inevitably be some disagreement.
Leave them all confined in their run for about a week and then let them out to freerange in the late afternoon. They then shouldn't roam too far and should find their way home ok. After a few days doing that you should be able to get back to their normal routine.
Good luck and have fun.