I have a D4 MCPCB at home. I will measure it just tell me what dimensions you need. In D4 the screw holds the MCPCB and two legs of the optics resting on the screw. So if we make like D4S and same screw holding down the aux pcb you need to cut off more from the legs on screws. Maybe you need use longer screws also.
Edit: I think less leds are also enough. like 6 or 8.
The resistors and the LDO costs in serial production less than 20 cents so why not stick it on it
Of course a sort of LVP like I am planning on my tail boards would be possible as well, but that costs like 0.6$ more
But pogo pins do need some support, they are long, thin and bendy. Which is why I suggested a 3D printed support.
Perhaps a big dollop of hot glue might suffice.
Back in the day my kit was designed for ATE on a GenRad/Teradyne bed of nails, with guided probe for detailed stuff. Everything made extremely precisely and solidly.
Not necessary for a torch. Just a common flashing interface.
I fear, you won’t have fun soldering pogo pins aligned with your design, lexel, something like this with a notch for automatic alignment might be better. Was still difficult to solder though, especially with iron, I was successful with hot air finally. But hot air might cause problems with a 2-sided design.
I’m hoping Hank might offer a flashing kit too, but I don’t know if that will happen. For now, I could stand to get some pogo pins (or really any pins) to put into my ribbon cable, since I haven’t had a chance to try out the flashing pads yet.