Out of a piece of 12″x12″ aluminum sheet metal, cut two rectangles and drill six rivet holes and four holes to attach the bill acceptor.
Cut aluminum angle into two 11 1/2″ lengths.
For each aluminum angle, drill and tap two holes; drill three faceplate rivet holes.
Rivet the two aluminum angles to each side of the faceplate. Allow room (about 1/8″) to overlap with the front of the box to create flush surface; make sure aluminum angles are positioned to lie flush on the inside of box.
Drill four holes through the box that exactly align with tapped holes in aluminum angle. (tip: if using acrylic, use an acrylic bit. If you don’t have an acrylic bit, set drill to reverse, and gently apply pressure to prevent cracking).
Measure 16″ leads, solder one end to barrel plug and other end to J2 connectors. Attach barrel plug to back of box. Tape leads to base of box.