Lister Fusion: How do I refit the clipper head?

Turn the clipper upside down and fit the top cover to the handle. Fit in the bearing carrier, then place the 2 black (14mm) screw in the screw holes in the bearing carrier and screw down until resistance is felt. Fit the gearbox/bottom cover over the bearing cover, then place the long M4 screws (35mm) into the screw holes in the gearbox/bottom cover and screw down until resistance is felt, ensuring that the 2 spring washers are reinserted or present in the holes. Fit the clipper head. Screw in the short M4 screws (16mm) to the holes in the clipper head. Turn the clipper over and screw in the clipper head front screw, tightening securely with the washer provided. Turn the clipper upside down again and carefully fit the top blade to the clipper head, ensuring the crank roller is located in the socket of the blade. Fit the bottom blade, ensuring the 2 holes are fitted over the pegs. Insert the tension bolt through the central hole in the blade and fit the tension spring over the tension bolt and screw the tension nut down tight until it stops. Then using the mark on the tension nut as a guide, slacken the tension nut back off 1 1/2 turns to set the tension.