The Mac SE and Mac Classic use different connectors on the analog board, the signals are the same, but this only works for SE 

All you will need is a RP2040 and four wires and a ground connection. Connect directly from the Pico’s GPIO pins to the analog board’s signal pins.

Flash the Pico with the firmware and connect the wires as follows

• GPIO18 -> DATA
• GPIO19 -> VSYNC
• GPIO21 -> HSYNC
• GND -> GND

The analog board must be powered independently — either inside a Compact Mac chassis with its original power supply, or via an ATX power supply providing +5V, +12V and −12V. Do not attempt to power the analog board from the Pico ;)

Warning:The CRT operates at up to 15,000 volts at the anode. Always discharge the CRT before working inside the chassis, and treat all high-voltage areas with appropriate caution. If you have no idea what I'm talking about, please don't go on 

GitHub repo available soon