Preparation

• 1). Place all of the 54-inch long material on the worktable. Position them so that the 54-inch length is running from your left to your right. Label the left and right sides of these pieces as the ends. Measure from the end on your left of each piece and make marks on the long edges at 3/4, 13 5/16, 14 1/16, 26 5/8, 27 3/8, 39 15/16, 40 11/16 and 53 1/4-inches. Put the framing square on the marks and draw lines across the material.
  
  
• 2). Drill pilot holes between the lines with a 1/16-inch drill bit. Drill countersink holes in the same place 3/8-inch deep. Make one hole 1-inch from the long edges and one midway between the two.
  
  
• 3). Put the five pieces of 13-by-7 3/4-by-3/4-inch medium density fiberboard on the worktable. Measure from one corner and make a mark at 3 3/4-inches on one of the 7 3/4-inch edges.
  
  
• 4). Position the framing square from that mark down to the corner on the opposite end of the wood and draw a line. Cut the line with a jigsaw. These are the sides and partitions.
  
  
• 5). Make marks 3/8-inch and 8-inches apart from one of the long edges of the 13 3/4-inch wide piece and the 4 1/2-inch wide piece. Drill pilot holes and countersink holes as before.
  
  

Assembly

• 1). Apply glue to one long edge of the 54-by-7 3/4-by-3/4-inch piece. Set it against the edge of the 54-by-13 3/4-by-3/4-inch piece with the pilot holes. Secure it with the drywall screws. Run a bead of glue on the two long edges of the partitions and sides and secure them with the drywall screws.
  
  
• 2). Mark and drill one long edge of the 54-by-4 1/2-by-3/4-inch piece as you did before. Apply glue to the tops of the partitions and ends as well as the top of the back of the box. Secure the 54-by-4 1/2-by-3/4-inch piece with the drywall screws.
  
  
• 3). Measure from one corner of the 54-by-16 13/16-by-3/4-inch medium density fiberboard and make a mark at 8 7/16 on the 16 13/16-inch edge. Put the framing square on the mark and draw a 24-inch line.
  
  
• 4). Repeat this from the opposite end of the piece. Next, make a mark on those lines at 7 and 20 3/8-inches. Set the compass at 5 5/8-inches, stick the point of the compass on the intersecting marks and draw four circles. Drill a hole with a 3/8-inch drill bit inside the circle, slip the blade of the jigsaw into the hole and cut out the circles.
  
  
• 5). Secure the front to the box with the drywall screws. Install the terminal cup according to manufacturer's instructions.