You can leave it in the same folder.
If the Vault Cache is in the UE installation folder (Program Files \ Epic Games \ UE_4.2X) you better move it to a new location (C: or My Documents, or some external HD / SSD)
Install Windows and also Unreal Engine. Then go to Epic Games Laucher, under Settings / EditVaulCache Location
And choose the new location for your folder.
It can be anywhere.
