I installed 2 x 300mm wire pull shelves in my Mum's kitchen prior to buying more for my own new house, she loves them, no bending down to see whats at the back. I fitted them by laying on top of the existing shelf to mark screw holes, same for the bottom one, just lay the shelf on the bottom of unit so it will be 15mm off the cabinet - simples - just one comment there are 2 metal protrusions on the wire 'basket' that can catch on the door and not sure why they are there. You can fit the door to the shelves but that looks tricky to work out how to get them centred on cabinet?