These daft things can be anywhere...however a popular place on these is the seat, so you have to be sitting on the thing for a start up, the clutch pedal and also the gear selector - so that you cant reverse when the cutters are spinning. How crazy is that? Seriously though, the only real way is to have a look underneath...if there is a lever or pedal there could be a switch nearby so look out for wiring. Any of these interlock switches will stop your engine cranking over - I've disconnected them on my machine.
John
July 2009