Eric,
I read this yesterday and decided to wait and see what you had to say about replacing the male fitting on the amp. I don't have any experience with Luxman so I can't answer your actual question.
With Furutech not being the pancea that most people think it is, you might try an upgrade to a screw type connector. Since you make your own power cables this would not be a problem for you and when you sell the amp, this would be a nice upgrade that should be positive.
The problem with this is that a quick search didn’t find anything I like at a reasonable price.
But I’ll keep an eye open and if you like this idea and find something you like I’m sure you will post it. I’m having a custom amp built and the power cables between chasses are screw type so I’ll ask my amp builder what he used.
I have a mill with a DRO so it is easy for me to drill precise holes so if you need an adapter plate made, sketch it up and I’ll be glad to make it for you.
Jerry