Rick- I had 2 Boxers at a time too, male and female.
I got Rocky in Spring of '92 and I got Tasha in Spring of '93, both as puppies. They had some time to work out their places in the family which inolved a lot of barking and nipping from the little girl, but Rocky just shrugged it off. I did get brand new beds for both of them as soon as I added Tasha to the family and Rocky was cage trained and they both slept where ever they wanted to for the first 6 months they were together. They just kind of became best buds within a week(Rocky was neutered) but she had jealousy issues that she woulda had with any other dog, just the type that she was.
You know how Boxers are- they're exciteable and full of energy- so I would be careful leaving them home alone to roam because they will no doubt get into everything in the crib!
JV