I've just done a job on the indicator/signal stalk of my wife's 1999 A-Class A190.
I'm not sure if this is the same as the SRT-6, but it looks like the same setup on the SLK32/230.
See attached post for removal/replacement - apparently a common design fault with the high beam locking on.

Looking for help with Headlight/indicator stalk.... - Benzworld.org - Mercedes-Benz Discussion Forum