This would be the place to do some research.
Personally I think you'll be wasting your time. The engine's all wrong for the frame and running gear; and it's not just the rocker covers.
The bike in in photo probably comprises a German equivalent to one of those dog's dinners of 50's, 60's, and 70's Brit-bike parts once only too familiar to those of us steaming round the North Circular in the late 70's.