Found this artical . . great reading.
http://time.fh-augsburg.de/~erd/Mode...ad/KwikFli.pdf
It appears the Mk III was (approx) 59" although 60" is getting a popular vote. Funny, I could have sworn it was 66" . . maybe I had a MkIII fuse with a Mk2 or Mk1 wing ???????
Jeff