"Stock interior look, keep you in the seat better". You left out any reference to safety of the occupant. I don't see what you have pictured as any solution other then stock look. The between the seats mounting angle is a huge compromise, you know that already, the width and shape of the seat back will only induce the v belt to slip off and down, and I'm on record many times of the risk of using any shoulder harness without a 5th+ belt. You need to widen your options, this is not it, IMO.