Ok so I kind of already made a post about this but still really didn't get my question answered. I recently bought a mesa boogie rectifier 4x12 cab and I still am unsure about which input to plug it into. Some people say one of the 4 ohm ones or the 8 ohm one. I'm assuming the 8 ohm is mono. I only have ONE head and want to be able to use ALL 4 speakers. So which one do I use?

Here's the jack: