Some additional information on the pictured cars:
The puzzle picture is taken from the first DKW 3=6 Monza brochure and is probably a retouched picture of the Monza record car which gave the well-known name to it (windscreen with rounded corners, but edgy side window cutouts, just one windscreen wiper). Body by Dannenhauer & Stauss.
The pictures in reply #2 and #13 show the second DKW Sportcoupé built by Dannenhauer & Stauss, built on the narrower F91 chassis.
The pictures in reply #3 and #12 show Monzas bodied by Schenk (cp.
https://www.autopuzzles.com/forum/2017-46/wendax-4192/)
The picture in reply #14 shows a Monza bodied by Massholder (#18 of 21 Massholder cars).