A method is described to implant a cochlear implant electrode into a cochlea having a single internal cavity defined by an outer cavity wall. An implantable electrode array is made of a resilient electrode carrier material and has an outer surface with one or more stimulation contacts for delivering the electrical stimulation signals to adjacent neural tissue. A distal end of the electrode array is attached to an insertion line made of a line material different from the electrode carrier material. The distal end of the electrode array is inserted through a single cochleostomy opening into the cochlea while an extra-cochlear end of the insertion line is held outside the cochleostomy opening. The remainder of the electrode array is inserted through the cochleostomy opening into the cochlea while continuing to hold the extra-cochlear end outside the cochlea to maneuver all of the stimulation contacts against the outer cavity wall.