At home I dive a 7-mil wetsuit (actually a 9/7/6 mil combination) and the Zeagle Ranger. I fine-tuned the weight distribution amongst a weight belt, integrated weight pockets, and trim pockets in a pool:
In full dive gear, but WITHOUT the BCD and tank, I put enough weight in the weight belt to achieve neutral buoyancy at 14 feet (the pool wasn't any deeper). My weight belt is multi-pocketed and I next distributed the weight among the pockets for best control of attitude. That is I could swim face-up as easily as face-down. I then adjusted a little more weight forward for a slight face-down tendency. At the surface, I checked that I could keep my head above water with only very gentle finning required. Write down your weight configuration.
Next it's time to add the BCD and tank:
By the way, with my body build I am head light and feet heavy So, I moved the Ranger trim pockets from their original downward-pointing position on the bottom tank belt to the top tank belt and pointing upwards. It took a small Velcro strip to do it. This let me add trim weight closer to my head.
So back at the pool, don the BCD and tank. At first adjust your front and back weighting ratio between the integrated weight pockets and the trim pockets to achieve your preferred face-up and face-down tendencies. Again, I prefer a slight face-down tendency (anti-turtle weighting). Next, fine tune the weight distribution so that you can hover in any, or almost any, attitude (vertical, horizontal, upside-down, etc). Again write down your weight configuration.
I dive both steel 100 and AL80 tanks, so I repeated the last steps for each tank type. I also checked the weighting for each tank type with a full cylinder, and one with 500 psi in it.
The last step involves recalculating the weights for salt water instead of fresh water. (Write it down). Next, dive and see how it works in open water. You may need some final tweaking.
Hopefully, this should resolve the "separation anxiety" involved with removing your BCD underwater.
Regards,
Carbon