Perch and Dolphin are two normally unattended platforms in Bass Strait. The jackets were gravity based and prefilled with iron ballast giving a lift weight of around 2200 tonnes. The design included padears for the lifting slings. These padears were located some 40 metres above the barge deck. Dr Keron prepared installation procedures for these lifts including design of guy wires to allow the lift slings to be looped around the padears without riggers needing to leave the deck of the cargo barge. Dr Keron also recognised that the unusual arrangement of two lifting slings close to the centre of the structure and three large weights (the filled gravity bases) some distance away could create a situation where one sling was overloaded. Special procedures to select slings of equal length and careful weight control of the mass of ballast in each pod were instigated by Esso. The two jackets were successfully set and their topsides installed over a 2 day period.