If replacing, remove the existing support arm by undoing the four screws using a 4mm Allen (hex) key
To fit the new support arm hold it in place with the left-hand end resting in place along the edge of the main body of the machine. Push the two long fixing screws through the two holes in the leg from the back, use the 4mm Allen (hex) key and screw them into the special fixing grooves in the back of the support arm, do not tighten them at this stage.