Other than the Volvo CD changer what have people been using as an after market CD changer for a Volvo CR 915 cassette indash radio? Also there is supposed to be a cable run to the back of the wagon (940), which connects to the radio for the CD changer, but where is it? Are the CD holders for a 10 disk changer universal for different brands, e.g. Sony fits in Panasonic? Thx.