is it possible to bond rabbits without an enclosure?/general bonding advice

i’m in the process of getting both my boys neutered (one was fixed last month and the other is going in later this month) and we want to start the process of bonding them afterwards. everywhere online and his vet is saying that they need to be in an enclosure next to each other so that they can see each other. we have x pens but i would be transitioning them from having access to their own spaces in the house to them being in the pen. how do i go about doing this? i spent so much time bunny proofing the house for them and it kinda feels like we’re going backwards. also literally NOWHERE in the house is neutral territory. they both take turns roaming around the house when the other is in either mine or my mom’s bedroom and i know it’s important to introduce them in a place none of them have been which isn’t possible in my case. also any advice on bonding 2 male rabbits would be great!!