I read your article about the multi head printer. I have a better solution for the temperature control.
Basically you get a cheap $15 industrial temperature controller with a k type thermocouple.
They have auto PID tuning, and really cntrol the temp much better than the thermistor machines.
I use them in my liquid cooled hot ends to run polycarbonate at 305c. Marlin has a issue with thermocouples and 2 years ago there was not much other option unlike now with the Smoothieboard, and Fastbot BBP boards that handle thermocouple inputs direct without a adapter board.
You will have to make a new heater block with a m6 thread or learn how to make your own that will fit in the thermistor mount. (I make my own)