This is my latest/ last release of MCP3304 which also includes averaging, raw, millivolts, volts, and other options for the data received from a MCP3304 ADC. I am hoping that this will be helpful to others who may have had issues trying to use a SPI version. This simply requires the correct pins. As for the hardware, it would be a good idea to use a voltage reference for the 5 volt reference required and as for the level shift from 5v to 3.3v, such as the Raspberry Pico, I utilized a MAX3377, but I'm sure there are many other options. Although this was specifically designed for use of the Raspberry Pico, I'm pretty sure that it will work with any board since it allows for input of each pin separately.