Question about: Self-illuminating markings

Hello together, I am currently working on my seasonal vehicle (pure meeting vehicle, no everyday operation) to clean the rear completely, i.e. i.e. no registration plate. Now I have got a self-reflecting license plate and would like to mount this at the rear window to drive on meetings with suction cups from the inside and then remove it again at the meeting. Does anyone know if this would be okay in the sense of the TÜV/Police? As said, I do not drive by car in the A The only thing I found in the net is “place, type and height according to EG-Rili 70/222/EEC of 20.3.1970”, which states that the registration plate must be mounted on vehicles starting from BJ 1.1.1983 > 1200 mm high. Please and hope on helpful answers DANKE! MFG