Finally got round to upgrading my BigBox Dual. Started with the easy part installing the screen. At this point I must admit it hasn't been powered up as the electronics is the next task.. I decided to keep it as close to the original LCD screen. This is made up with laminates of 3mm and 5mm red chilli S4 4T50. The interface layer is 5mm secured to the original frame by a couple of top side bolts (18mm), the other holes are either 3mm through hole to the original nut traps or 2.5mm then tapped out to M3. The bottom middle and top middle layers are identical 5mm sections. The middle middle is 3mm with a cut out for the memory card. The top layer is 3mm with a couple of 8mm bits of aluminium rod cut into 5mm lengths to act as buttons. The screws used were M3x40mm cap heads, 4 off cut down to 20mm and 6 off cut down to 35mm which connect to the original nut trap, I had forgotten how much fun they could be. For mounting the PCB I threaded the holes then countersunk them from below. 5 off M3x20mm countersunk. then used extra nuts to act as standoff (I made some spacers but my perspex had a slight size difference that I hadn't taken into account of 0.5mm per 5mm slice, if I had checked I could have had it level by mirroring the design but hindsight is an exact science). Any questions or improvements let me know.