Making measurements of the trestles dimensions has shown a large area at the back of the work bench. Which is ideal for electronic test equipment, solder iron etc.
By adding a small steel plate to the back of the bench to fix a magnetic kidney bowl, which is perfect for screws and metal parts when dismantling electronic devices. 
A series of holes for more tools at the back of the bench for general hand tools (screwdrivers, pliers etc.), this is a great addition to the extra shadow boards on the sides of the bench.