Oh, they look just lovely

Congratulations!
I got Hillie (my Jersey) home as 2-year old in-calf heifer, turned out to be three months before she calved. She was quiet already; you could touch her while she was eating cake out in the field. The owners had her running about in the cattle shed getting used to more human contact for a week before we picked her up. Once home, she was coming up for strokes within a week. Mind, she didn't bring a friend with her, whereas your two may be a bit more self-sufficient as they're already pals and coming together.
Hillie has always been tied by the neck for milking. I did a lot of handling, and messing on with the udder, from the beginning, then as she approached calving got her used to coming into the stall, eating cake, being tied up, having her udder washed and handled. I never restrained her other than by the neck chain in the stall for milking, and she soon got used to what she had to do.
I have tried her with a halter a few times but she really doesn't like it. She's fine with a neck chain or rope, so I just use that. I halter-trained her daughter as a young calf, and she's fine with it. If I really needed Hillie on a halter I would get one made up to fit her perfectly, and persevere, but she's so easy to manage I haven't felt the need.