Remixed TeachingTechs electronics case to fit this 30 amp relay (affiliate link). The 10 amp relays work fine if you're switching power on the A/C line in side, but if you want to power a Pi on a DC to DC buck converter you need to put the relay on the 24VDC line, and you need a 30 amp relay for that. Original itructio are here: just use the file all_in_one_ender_3_case_-_left_case_-_raspberry_pi_buck_and_30a_relay.stl for the left side case.