Here's what I've found. Critique away! Please?
edit: I'd like to provide the .pdf's I referenced as courtesy to those who wish to review my findings.
https://frank.pocnet.net/sheets/093/6/6FJ7.pdfhttps://frank.pocnet.net/sheets/093/6/6DN7.pdf6FJ7 6DN7
Pin 1 -Heater Neg- Pin 8
Pin 2 -No-
Pin 3 -Grid Section 2- Pin 1
Pin 4 -No-
Pin 5 -Plate Section 2- Pin 2
Pin 6 -No-
Pin 7 -Cathode Sec. 2- Pin 3
Pin 8 -No-
Pin 9 -Cathode Sec. 1- Pin 6
Pin 10 -Grid Sec. 1- Pin 4
Pin 11 -Plate Sec. 1- Pin 5
Pin 12 -Heater Pos- Pin 7
The only hiccup I found was the resistor on pins 8/10 - I could keep one end of the resistor on pin 4 of the 6DN7, and attach the the other end to a solder post I would mount (I have single tag boards), and wire to the potentiometer. So this is why that mysterious hole is there!!! Maybe. I'm on to you, JHPJPBDOC....
Other than this, would it be a direct swap, check voltages, and fire away? Hopefully no fire. Just glow.
I do like the way they look, and everyone is crazy about coinbase 6dn7's so I thought I'd pick some up. That's about it, lol. Also, it would just be a fun experience to figure something out and accomplish a conversion like this - in honor of the 6DN7 who once ruled over all S.E.X.. I didn't know that when changing pinouts all you need to do is reconnect to the new pin. I thought a circuit redesign would be in order or something. Learning something new every day here.
Thanks for the input
Maybe an adapter project for the 6FJ7 would be next.