@Andy_Mac - made a new thread, as to not thread jack that Forester thread.
Just checked my car - it does have a hollow shaft, where the lockout cable comes up.
Also looking at partsouq, my S401 has exactly the same shifter rod to a 2001 GDB V7 Impreza STI (Dad's old STI) - 35011. They used that rod up until the end of 07, when the GD chassis ended.
The Raceseng one says it's for a 04-17 STI (Handle and Base).
Being USDM, they only got the STI in 2004, which I believe is the V9? So still a GD chassis, and should be the same as what I have (no factory VIN available to confirm this).
So going off partsouq - I should have a Impreza STI shifter etc, and should be sweet with Raceseng's one?
I was gonna ask @mtbtimr if he would make me one up, for a price of course. Would happily pay a premium for one from him, over an internet bought one.