The SMG is the manual 6-speed tranny, but the clutch is replaced with a computer operated pump and piston. There are conversion kits to allow you to remove the SMG gubbins that bolts to the transmission and fit a normal clutch slave cylinder and a clutch pedal inside the car. There is bound to be a thread on here somewhere on how to do the conversion. Failing that look at realoem.com to identify the parts you require and go from there.
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