As there are only a few components and a single module build instructions are probably not required, simply match to available images.

The ESP32 module mounts on the underside. The caps and resistor networks have silkscreen on top but should also be mounted on the underside (making sure polarity is correct for capacitors), this allows us to reduce the profile of the enclosure.

Pin 1 of the OLED is Ground, pin 2 is VCC, so make sure you get an OLED with this pinout (versions with pin 2 Ground and pin 1  VCC are also available so be careful. The OLED mounts on top, keep the pins short as possible, trim if possible...

The second RJ12 connector (ST4) is not used in my version, the board supports it but we will need to modify the current 3D enclosure to allow for the second RJ12 connector... perhaps later when I have time...

There should be no need to remove the PCB to reprogram it, simply plug in the micro USB cable in the top.