[Marc-André Haldimann]

Nick,

You're correct: most of the pictures are published in Janda and Poruba 1997, p. 2-12. They date probably from September 1943; WNF was building by then this mock-up for sending it to for presentation to the employees of E-Stelle Rechlin. The prototype is known to have been at Rechlin by 10 October 1943.

Source: Janda and Poruba 1997, Messerschmitt Bf 109K, JaPo, p. 77.