done that
I have personally used both methods to raise the swing keel on my 22. Once when the cable became tangled on the keel winch drum, I drove the boat to shallow water and was able to raise the keel and thus take tension off the keel cable and untangled the mess. Another time I unloaded the boat from the trailer without the cable attached to the keel. (don't ask how that happened). The boat slid off the trailer and the keel gently extended to full depth. Since I did not know this, I went sailing and when I went to put the keel down, discovered it was already down. How to get it up. I had heard you can walk a stout line from the bow and under the boat back to the sheet winches. I elected to go into the warm waters of Biscayne Bay with mask and snorkel to make it happen. It works best, because you get more leverage on the keel, if you keep the line close to the tip of the keel. This reqires some underwater finesse to make the line just right. Then it is possible to tie one line to the port winch and crank the other line taut with the starboard winch (this must be reversed in the Southern Hemisphere). It is hard, work cranking the keel up this way but definitely possible. Cautions: the line will very quickly wear a groove in your rub rail, use a chafe guard, STAY AWAY FROM THE KEEL WHEN CRANKING IT UP.