Case for DIY programmable resistor matching 2.54 mm PCB circuit board spacing

Here you can see the housing for a DIY programmable resistor. For copyright reasons, the temperature symbol is not included.

The LEDs are controlled by a PWM signal from an Arduino. The brightness of the LEDs is modulated via the PWM signal. As the brightness changes, so does the resistance of the photoresistors. Functionally, this is an optocoupler, but the key feature of signal transmission is not used in this circuit.

In case you're wondering why I didn't use a prefabricated module, this case is part of a project to convert a VW Golf 3 speedometer cluster for a truck simulator. The two gauges in the speedometer cluster for temperature and fuel level actively measure resistance.