I am hoping to power the Raspberry Pi server running Octoprint that I've got stored inside my printer from the printers PSU. That would mean the only wire coming from the printer is its own power cable. That would be satisfyingly neat. Can anyone recommend which terminals might be good for this? The amperage coming from the PSU seems to be too low. My Pi boots but the Wifi never connects so I assume the peripherals aren't getting the power they need. Could you also recommend a good voltage regulator to step the voltage and current down to about 5V and maybe 3A?