Sorry for the long wait to hear the result. My computer crashed badly and I had to start again. The little hole I saw was indeed a grub screw and with its removal it turned out to be a really hard job to knock it down and out. So little space to work in. I thought I was going to break out the bottom weld, but eventually i succeeded. The problem was the dust of ages had built up over time.[It is now 25 years old]. There was not a sign of rust. It now has a grease nipple installed so the job won't happen again.
Thank you again Gadge. Kind regards, Aussie
