1. Remove the boot clamps and collapse the boot if equipped. On upright and inverted models, loosen the set screws and remove the housing cover by rotating CCW.
2. Remove the protection tube and check to see if the lifting screw has travel stops. This may require the use of a pipe wrench or strap wrench. If the screw jacks has travel stops on the screw, these will need to be removed before the lifting screw is removed from the screw jacks. If the screw jacks does not have stops, the lifting screw can be removed by simply unthreading it from the wormgear.
3. Remove the thrust bearing / tapered roller bearing and the worm gear from the sleeve. The bearing cones may be pressed onto the wormgear.
4. Keyed screw jackss have a keyway cut the length of the lifting screw. The steel housing cover has a key, which travels in the keyway and prevents rotation of the lifting screw. It is very important to prevent any side load on a keyed screw jacks, as the key can cut into the lifting screw, and severely affect the life of the screw jacks.
5. Remove screws, from the bearing covers. Remove the bearing covers and seals carefully to avoid damaging seals. Make sure keys have been removed first. 
6. Carefully remove the shims from the screw jacks sleeve or bearing cover. Note: there will not necessarily be an equal quantity of shims per side. Keep track of the number and order of shims on each side of the screw jacks.
7. Remove the worm shaft bearings. The cups may be press-fit and require the use of a dead-blow, plastic or other non-marring mallet to remove the worm.