Raspberry Pi 3B enclosure with 40mm fan for Kintaro heat sink

This is a case for the Raspberry Pi 3B with a 40mm fan that fits the Kintaro heatsink. The case reduces standoffs at the bottom so that the Pi remains level despite the use of M2 nuts and bolts to mount the heatsink. In addition, the case provides space for a 40mm fan and exhaust vent holes on the top that are tall enough to fit over a heatsink. A 40mm Noctua NF A4x20 fan can be added to the case, but it may require a slight push to start when wired to 5V via the GPIO header.