Harken 7413.10 MKIV Jib Reefing & Furling built after Feb. 2009 - Manual (Page 27)

Commissioning—Unit 3, 4 Turnbuckle on Boat
MKIV units 3, 4 27
Have extra cotter pins and locknuts on hand to replace used ones at
base of unit and for turnbuckle.
Hold foils and loosen drum assembly screws until you can pull clamp
out to lower foils.
Lower foils.
Remove link plates.
Raise drum assembly and use halyard to lift and hold it about 1.5 m (5').
Raise foils using second halyard and secure. Allow room above for
turnbuckle take up.
Adjust turnbuckle.
Replace used cotter pins and locknuts. Lower drum assembly and
install clevis pin and new cotter pin.
Lift foils so top is 25 mm (1") below upper terminal.
WARNING! Make sure drum assembly and foils are
securely lifted with a halyard before adjusting turnbuckle.
Foils can drop suddenly, causing injury to hands.