Fox,
I had the exact same problem when trying to replace the park brake cables on my 1953 3100 (US version). The ferrule on the end of the cable simply was too large to fit into the bracket. So I did some very judicious filing with a rat tail file, checking often to make sure that I didn't over file the bracket. Once it was close, a drop of oil helped ease the cable end into the bracket. When I tightened the bolt on the bracket if worked as it should.
