G'day Snake Farm, that Willys was made from a sedan, the opera windows are part of the sedan roof, using glass coupe 1/4s. It's a pretty neat looking ride, really captures the style of a late 60's early 70's weekend warrior.
Willys were mainly assembled down here buy Holden Bros(Before GM got their teeth into Holden), they were body builders in Melbourne. Holden held the Willys contract from early 30's until 1936. In 1937, another company TJ Richards won the contract. TJR bodies were a very close copy of what Willys in the US were building, with the exception of the coupe. TJR built theirs as a 5w using sedan doors. I had one for quite a few years but never progressed far with it. I sold it to a guy in the Northern Territory last year. I will attach some pics so you can see what they looked like.
Cheers
Andrew