Could anyone be so kind as to tell me just where I may find the "accident fuel cut off" aka reset switch aka inertia switch I hear and read about - in my 1990 300SL?

I had a minor accident and now the car won't start althought the car has 1/2 tank of gas and the battery is fine [clock is still telling correct time etc]

I can't find any reference to the switch or its location in the owner's manual.
Thanks in advance!
Doug