I am breathing and making a point to breath in a controlled fashion. Raise lower & stabilize what exactly? I transition from vertical to 35* slowly and in a controlled manner not taxing my core or body in the process. For the first 5 minutes or so I am fine and the stretch is good. Its only after about 6-8 minutes do I start to feel nauseous.
If hanging upside down is too much, there is a somewhat lesser but still effective alternative. I did this ugly cartwheeling 100 foot crash downhill skiing and pinched several nerves in my neck and I just couldn’t break the inflammation cycle and get better. PT set me up with a sort of neck stretcher that pulled up on my head using a webbing under my chin and rear of my skull, with a rope and pulley arrangement with a big graduated water bag for weight. A couple weeks of that got me on the road to healing. Hanging upside down is sort of all or nothing, while the water bag allowed for close weight adjustments and maintaining a high level of comfort.