This is a stackable housing for the (adafruit) v2 motor shield compatible with the fischertechnik construction system.
For the base case, assemble without stacking headers. Do not install the supply voltage jumper pins and the servo header. Both are useless and in the way for the case.
Use SPAX 2.5x12 wood screws for the housing.
Connect SDA, SCL, GND and +5V from the shield to the 4-wire ribbon cable at the base shield, and you're set.
For the stacking shields, you don't have to connect any wire, but you'll have to set the I2C address by jumper accordingly.