Ohh ok... So you were looking more for how to lift
the boat in order to work
on the keel? I thought you had that part covered since she's already on the trailer
and you were looking for info on the keel string indicator. Which I'm still not sure what that is-as I only have a keel cable on mine and that's why I asked for pictures.
I had to remove my keel so I was faced with the same dilemma of lifting the boat. What I did was lower the nose of the trailer as low as the jack would go. At this angle I was able to get cinder blocks under the stern. Once in place I raised the nose of the trailer until the stern was resting on the blocks instead of the trailer. I then placed blocks mid-ship and under the bow and lowered the trailer again. Voila, she was up on blocks...