Without taking it off I don't knowAll picks are top down so can't see. I believe it's 25mm and goes over the sai pipe.
Why you so keen to see my car ??Vr6gordy, Im keen to see your car in all of its glory. Will you shed any light on if this will happen?
You could do but what I also forgot to mention which is also a a key power point is the Ram Air effect which you no longer have. Cars run better with cold air and that includes NA cars so moving the filter say down to the bumper intake area will help a filter but it's still not great. Now if you fitted say a BMC/CDA and had a feed pipe running from the lower bumper then you might see some gains but in its current state forget it.
Just took a look and they all look K04 based so the stock air box should still fit with no issues