I have heard that the ship is lowered to the level of the wharf, then rails are fitted between the ship and wharf. The crane is then winched onto the wharf.

But as that movement is at right angles to how it will eventually operate, separate wheels are used for transport under 2 inner set of legs the operational wheels are fitted when the crane is in position on the wharf.

There is a video of the operation on the video page. Search using "Gateway gets 2nd batch of cranes, and claims 1M TEU "committed"" or part there of.

One word - impressive ! But exactly how and what do they use to remove them from the deck ?