White Lenses
I believe that the reason for the lug is so you don't put them straight on with clear bulbs, some sort of law in Germany so I'm told, but then again that could be a load of old bullocks !!.
Any way, broke two, then found the stem is thicker on the white ones and the lug to file off, so filed some off the depth and width of the lug and pushed the lense in from the middle, and they all poped in great.
If you push in from the opposite end it will break off the stem.
Gary.
motor works, £15.50 for 4 lenses and 4 bulbs.