Mounting depth in door of 02 coupe, 6.5"
 

So, I'm looking to replace the speakers in my 02 coupe. I've done a lot of searching, but haven't found a clear answer to my question.

What is the maximum mounting depth allowable in the doors of my 02 coupe? I think it's around 2" with no modifications, but how much more can I gain with a spacer ring before I run out of room?