All of the larger Anderson style connectors I've seen installed on panels have been screwed in through the hole in the center of the connector itself. They cut a rectangular hole that's slightly larger than the Anderson connector, that was butted up against a wall. The connector was then bolted to the wall, and you can plug in a wire easily.
You can see in the picture in the link below where the connector is just a rectangular hole with a flat bracket behind it.
Feb 15, 2019 - Find many great new & used options and get the best deals for Genuine Anderson 50A Connector To 12V Cigarette Lighter Hella Merit Plug Adapter at the best online prices at eBay!
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II think this might be the specific product that you're looking for if you're not opting for a do-it-yourself option.
175a Mounting Kit. 175a Mounting Kit, 2 Plugs. Mounting Kit for 175 amp Anderson Plugs, suits all types of 175 amp plugs. Anderson Plug Mounting Kit Options. A locking tap that goes on the plug being inserted prevents the plug from accidental removal or rattling out.
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