Possible to add battery posts to side terminal?

My new car stereo system was connected to the top battery posts, while the car's electronics remained on the side posts. When Sears replaced the battery under warranty, I lost the top posts. They told me that the new design for DieHard Gold Advanced does not have four posts any longer (like the old DieHard Platinum). So right now the car stereo system is disconnected. I'm thinking that the simplest, most flexible thing to do would be screw an adapter post into the side terminal, and then I can add the fancy Rockford Fosgate post clamps onto the side terminal. At least that's how I imagine it.. What I'm not sure about is whether there is a post adapter that has a screw thread and base that will also hold the side ring terminals (going to the car electronics). The side post adapter products that I'm looking at have short threads that go into the battery and they don't look similar to the side post bolts that can hold the side ring terminals. It looks like existing products make me choose one or the other, but I would like to have the adapter hold the side ring terminals plus have posts sticking out. I'm hesitating to change the fancy end of the existing stereo power wires from a post clamp to a side ring terminal because in the future I might decide to get a completely different battery like the one I had before.

I've seen both the short and the long adapters at Autozone. Alternatively, you could connect your power wire to the battery lead post on the alternator. That's what I did.My ex once told me I have a perfect face for radio.

How would I attached the Rockford Fosgate terminal to the "GM Side Post Battery Post Adaptor - Short" product? My audio system uses these terminals: http://www.rockfordfosgate.com/products/details/rfdb4 I saw this kind of post adapter at the auto parts store, but it doesn't look like there is enough thread because of the plastic shroud on my GM ring terminals: https://www.amazon.com/BASTC-MTX-STW-Mount-Battery-Posts/dp/B004GE6CDA Then I came across this style adapter which has some "stepped" cutouts at the base. Maybe this is what I am looking for, I am not sure. I don't know if this stepped base would mate with the GM ring terminals: https://www.amazon.com/gp/product/B0049BJ6CO https://www.amazon.com/dp/B00FDXL0BW/