Two of my mares, Juno and Havannah, have been joined at the hip since I brought Havannah to my new farm. I've always been able to ride one or the other in my arena--about 200' from my pasture--and the one I'm riding is quiet with me, but the other one will either run the fence line--Havannah--or call some, which Juno does. However, if I try to ride one from the barn, even the one I'm riding gets anxious.
Do you have to ride in your field, or do you have an arena? Can you ride from your barn? If you can ride from your barn, leave Pipe in the field and get on Taylor. Ride Taylor from the barn until you feel that he's right on the verge of getting anxious--as little as that may be--then turn him back. Don't let him get scared, but turn back right before he's becomes upset. You don't want to reward him for getting anxious--which you would do if you turned back WHEN he gets scared--but you want to reward him for remaining calm. That's why you turn back BEFORE he loses himself. Every time you ride Taylor from the barn, make it a bit longer. Hopefully, you can do several tries a day. Pipe will freak out, but he won't hurt himself. Go ahead and let him run the fence line. Try the same thing with you riding Pipe and leaving Taylor.
If Taylor is calling, too, and won't leave the barn with you, you need to do more work with both of them to get them to recognize that you are their leader and protector, and one does not need the other one to be safe, just you. If you've never done any work like that before, you'll need a professional to help you. There's not enough room on this forum to cover how to become a leader for your horses.
I rode Havannah from my barn last summer the way I just described, and eventually I was able to get her about a half-mile away. She never called for Juno but Juno called for her some, though not too much. Havannah DID balk at leaving, however, and I had to get pretty big with her to get her to move forward, but she got better and better the farther away we got. I still need to do more work with both Juno and Havannah to get them comfortable with leaving the other, but it will come. However, I couldn't do any of this if I didn't have both mares recognizing me as their leader and protector
I hope you have some luck with this.