an apparatus for replacement of a swivel atop a first , operating foundation on a turret of a production ship or offshore platform comprises a swivel lifting and moving apparatus for taking a swivel off or replacing a swivel on the first operating foundation on the turret and a second storing foundation spaced from the turret . the apparatus also comprises storage for supporting and moving at least one used and one spare swivel in connection with the second storing foundation , and a guiding system on the first and second foundations and on the swivel for accurately positioning the swivel onto a desired foundation .