Well if the trip isn’t too stressful for Chief, I’d say do at least two dates. You should use the litter box lined with hay so that you can have easy access to the bunnies if something goes wrong. You’ll usually know almost immediately if it won’t work as either bun has their ears back, tail up or are constantly charging/boxing the other rabbit. It is sometimes hard as you are terrified that something bad will happen but truth be told, as long as you are quick, there will rarely, if ever, be any sort of injury to either bun. Maryann literally lunged and bit at the second female that came into the enclosure but being buns, the other hopped quickly away and all maryann got was some fur in her mouth. But this is an EXTREME reaction. I witnessed Maryann and another bun circling each other and nipping for nearly four full seconds before someone was able to seperate them with the dust pan – and neither were even injured.
The main tell-tale signs are the bunny’s ears. If they go up, you will probably not need to worry about a vicious attack. Once they start to move after the agressive petting you give them, just watch. If either begin to flatten their ears or look somewhat aggressive, start petting them again at once for another 30 seconds or so.
You may also want to try them out of the box after a little while. Maryann would dominate the other buns and while she sat there cleaning herself and grooming, they’d just sit there. So pull them both out of the box and get the box out of the x-pen. Again, always give them good praises and pets when they encounter each other but don’t attack. When the buns I was working with would come nose-to-nose, I’d give them two seconds to see if either one would begin grooming or anything else, then I’d immediately say ‘gooood bunnies!’ and start in with the pets again.
There is bound to be some agression from time to time. Love at first sight is rare. Just make sure you have the dust pan handy and be confident.