Where does your battery negative connect?

On my Slant with A/C, the ground is connected to the A/C housing. Now you guys have me wondering if that is correct?

I don't think it matters electrically. Mine was grounded where the power steering pump would be. I have manual steering. I think it all depends on what accessories the car had. I wouldn't worry about it as long as it is grounded good and has all other grounding wires and straps we've talked about here.