Hi Steven,
On my P275 there are two eye bolts in the keel. One is attached to the dynema lifting rope. The others is a wire attached as a depth telltale. On the external end of the wire is a loop. When the keel is fully up, I insert a metal bar through the wire loop then lower the lifting rope until the bar straddles the keel box and takes the weight off the lifting rope. I believe this is a standard arrangement. I used to have a P21 but can’t remember if the setup was the same. I think it was.
I have now modified my wire strop so that it contains two loops. The loop at the end holds the keel fully up. A second loop halfway up allows the wire strop to support the keel when it is halfway down. Now the keel is either supported all the way up on the wire strop, halfway up on the wire strop or fully down supported by the keel box. The lifting rope is only used to move between these positions so it has an easy life and does not need a clutch to take the weight.
If you’d like to chat more do give me a call. I am P275/25 in our handbook.
Cheers - Ken