GROW45
There were two operated by Kuwait Airways for the Kuwait Oil Company in the1960's. I think that they ended up in U.K. eventually. What happened in between is very interesting but you would need to contact the Kuwait Prision Service to get the details! I have fond memories of the machine esp. the Bicycle mechanism which operated the flaps.
There is a great video of a Twin Pin airtest but I would need to contact the author before releasing details. If you are interested post a reply.
Rgds. FaPo Gai.