My Adrenelin defender 300 lock has just arrived , looks good . And not Sussed. It out properly yet , But it looks like it will go where the ardcase.one does , only your heels would be on the extension plate on the inside , need to take a pic . But if I can make a clip/bracket to hold it there it would be handy .
On short runs I park mine in the passenger footwell. For longer journeys or when carrying a passenger it fastens with a short chain wrapped around a rear seat frame and with the lock pin through one of the chain links. I dread loosing the key (I keep a spare key) as it will be an enormously difficult job to get it off without one. Which also happens to be a very good reason to fit one.
With regard to all these answers I am left not knowing which would be the best for my Series 3. One short answer would be great and I thank you in advance.