terry,
the working mechanism of the lifting keel is easily to see after removing the table from the keel housing.
If you want to renew the cables, the procedure depends on where the boat is (in the water or ashore). As you have to lift the keel nearly 20 cm above the housing to reach the bolt, you must find a way to support the keel from below. If ashore, you should first support the keel, build a wooden rack around the table to support the rectangular case of the winding mechanism which is necessary to move the keel from the upper position into a higher position until the bolt is free. Then, after supporting the keel from below, now in its higher position, take away the bolt and you can replace the cables. Take care that they have exactly the same length. If the rack is high enough, you can use the opportunity to clean the keel and apply an anti-corrosive to the upper part which is normally unreachable.
If the boat is not ashore, you would have to do the same as we did two years ago: Find a crane which lifts and holds just the keel by a belt, open two holes on both sides of the keel housing to reach the bolt, take it out, replace the cables and close the holes with two peaces of grp and some screws. Caution: These points are below the waterline.
When changing the cables, check the point where the they enter into the winding case, sometimes one cable scratches along the sharp metal.
Hope this helps
Gerold