The DRLs are identical in size to the original foglights and use the same mounting points on the bumper, no alterations to the vehicle (other than the obvious electrical connections) are needed so the car can be returned to original spec if wanted.

(Image from https://www.tuningversand.de/product_inf ... fisch.html)
They currently cost from 90€ to 119€ depending on where you buy them from. I ordered a few pairs together with some friends from tuningversand.de, 90€ per set (including relay and wiring harness) plus 18.90€ for p&p if you happen to live outside Germany.
I will be fitting them to a 225 front bumper when (if) I manage to find one. The original foglights are quite useless anyway so I personally prefer having running lights.
They're marketed under the AuCo brand of Germany, anyone know if the lights are in fact the same design that the Cibie brand of Valeo was marketing a few years back? They look a lot like them anyway. For some reason Valeo decided to abort the production of their LED DRLs before it never even properly started (plus pull the plug on their Cibie tuning brand at the same time....), wonder if they sold the design and rights to some (Chinese) manufacturer who now produces them for AuCo???