When errors are made, one has to take responsibility and solve them, and you are all too good noticing my errors, that's why this deserves an entire episode.
I've made a few letters with my big printer, two parts, the exterior/back in black PLA and the top/front cover in white PLA as a diffuser. Inside a few strips of WS2812b leds, a batterie, a 5v to 3,3v converter and an esp8266 that allows each letter color to be changed, hell'a'cool letters these are!
This is my first self made big printer, it is a bit rough around the edges but I've printed with this one an incredible amount of parts and is tremendously reliable (if you know how to treat it). There are no plans, models or STLs of this one, I designed it on the fly modifying and reprinting things as needed, I'm not sure if even I could replicate it.