Hi Michael, Hope you enjoyed your sail the other day. We past you near Chichester Marina.
To add to the other advice, Chichester Marina will lift you into there slings on a Friday afternoon, last job, and leave you there over the weekend, and drop you back first think Monday. This gives you almost three days to work on your keel. Of course it is not free, but you get a long time in the hoist for just one normal lift fee.
Alternatively, with your boat on trailer or cradle, ask a yard to lift the keel straight out through the top. You just need to unbolt the stainless steel bracket in the top of the keel. Make sure you block the keel underneath first. The keel will then come straight out.