Hi mate The PV PCB I'm using is the latest 'DINK' kit . The board measures 159 X 56 mm. Your box has internal lid fixings which compromise the useable area. Even without them its still too small. My printer is pretty accurate. I am using a SCAD box file (with external lid fixings). These things happen. I'm printing the lid to my SCAD box to make sure its ok before I make the box.
BTW I printed one of the lantern 'hanger' parts and the bearing lugs were very weak and snapped when tested. I saw that the lug had very little infill inside. So I increased the infill and added some extra diagonal mesh, and the whole thing went 'pear shaped' and failed to print properly after about an hour . I'm still a bit noob at this. I'm watching via a remote camera just now and my box lid is printing ok so far.
Have a nice day!