The Interface Box case needs to have the two DB-9 connector holes notched and also the mini USB port along with a hole drilled for the gate status LED and a hole for the phone jack (start gate). You also need to drill the Standoff holes for the breadboard. Position the breadboard inside the case and mark the position of the four holes to be drilled. Drill these 7/64 holes and install the standoffs. Temporarily set the breadboard on top of the standoffs to determine the height for the USB hole and mark accordingly. Cut out this hole using a nibbler or file and make sure that the hole aligns properly with the USB connector on the MicroController breadboard.

Now on the opposite end of the box mark and make the DB-9 connector holes in the center end of the box using the DB-9 connector as a template. Go for a tight fit because the connector doesn't allow for much clearance for the mounting screws. Do not mount the connectors or Breadboard at this time. See Photo.