Many thanks go to: 
Hot Rod Al  ex-Research Specialist at Playing Mantis.
Marsboy  for the initial write-up on the ancestry.
Wyatt  for the engine pics and very large JL reference pic website. Thanks for the pic links too.
Rick  for the White Lightning website (lightninglane.com).
pms485 (Mike)  for the excellent illustrations I've used, including the site logo.
Playing Mantis  for making all of this possible.
RC2  for bringing back the Spoilers after a 3 year hiatus.