You are more or less right. Off with the power supply and unplug at the wall. Disconnect the water supply and lower the waste pipe to the floor and drain it onto a towel until its empty. You may well have to access the element from below. Would recommend taking a photo of the wiring before you start to remove anything. You will find the element has a couple of chunky pipe clips holding water pipes to it, and a few screws holding the element case to the frame.
It's really just a fitting job