What are the options for the Nato plug in the back?

[INEOS OG]

Do yourself a solid and put some lube on the socket dust cap threads and the plug screw ring threads while you're messing with this project. A few folks have had seized caps. The alloy threads do like to corrode and gall up a bit. I'm using an industrial petroleum jelly but anything that won't react with the cap seal will work. A lanolin product, a dab of rubber grease, etc.

Thank you for mentiining this. I read about that issue as well. Some caps were seized on requiring replacenent of the plug.