I highly recommend against SOB carry. The hollow spot where you plan on putting that piece of steel, is there for a reason. If/when you fall on your back, the muscles on both side of that hollow spot, act as a cushion and absorb the impact far before the spine comes in contact with something hard. Put that piece of steel in that hollow, and it will transfer the energy of an impact directly to the spine. I am not a doctor, but every time I have fallen on my back, I was glad it was the muscles that ended up sore and not a broken spine.
Did you have a holster that didnt work for you SOB?