The lathes are shimmed to the bed/tray that is the last thing i would want to take off.
I think you're worrying too much: just make sure the shims (if any) go back when them came from. Those Master beds are built like a brick outhouse they'll bend the stand before twisting ;) And, if memory serves (ask Tony at lathes.co.uk for chapter and verse), the heads were dowelled after alignment so even removing the head would not be the end of the world.

In bits, the job looks safely do-able with a low trolley, plenty of wood, and an 'A' frame hoist to get you over the steps.