Many thanks for this! I found getting the screws back in very tough, especially as I was working alone. In the end I fitted the screws and washers loosely (couple of turns) with the locating ‘hooks’ on the washers rotated 45 degrees ‘up’ from their final position, then forced the spring end under the washer, before finally rotating the washer round to its final position (using a pair of pliers) and tightening the screw. Also, in order to minimise tension on the springs, the screen needs to be pointing up (when viewing the computer as if you were using it), not down. And lastly, don’t be alarmed when the screen doesn’t stay down once you’ve fixed it - it requires the weight of all the other parts to balance properly and will work once the computer is fully reassembled.

I found it tricky to get a grip on this connector with the PSU still in place so I left this step until I had removed the torx screws holding the PSU in place. By lifting the PSU and rotating it toward the top of the iMac I was able to disconnect the DC cable easily.