Hello Rich,
I also have an Oday 20. My swing keel was actually a bit loose. I had a slow leak coming from the front brackets of the swing keel. I have also replaced the pendant line going to the back of the swing keel.
If you crank the trailer jack all the way down, you can set wood blocks under the bottom edge of the transom. When you run the jack all the way up, the swing keel should just lift off the trailer enough to have some slack.
I used a couple of concrete blocks with 4x4’s.
I was able to adjust the trailer stands doing this too. Just go slow.
You should then be able to find the binding in the keel slot.
I wouldn’t recommend leaving the boat like this for any extended time, as it puts quite a strain on the front bow line.
I would also suggest chocking the trailer tires as the weight shifts.
To change out the pendant line required a lot more cribbing and a hoist. I took mine to work and used a forklift and large nylon rigging straps.
You might be able to do it with alternately cribbing the transom and adding blocks under the front end of the hull, but I would hate to hear you were squished.
Regards,
Todd