There are legal minimum heights for DRL that were on the hella website. LINK
I think that link is quite confusing the way they have set out where the lights are permitted.
Looking at the maximum hight the lights can it looks as if they must be below the headlights.
Yet the maximum height is 1500mm or do they mean it must be under the headlight up to a maximum height of 1500mm? If so then they must have different regs for lights actually in the headlights i.e. the Golf