I have a set of Polk Audio DB6930 (6X9 3-way) speakers to install in my 850. I could not get these guys to fit within the orginal enclosures from Volvo. It looks as if I will have to cut into the rear deck of the car. I prefer to avoid that if at all possible, any body do something similar to fit 6X9's in their rear? I am open to suggestions. Thanks in advance...