I have attached a picture of my '88 Convertible that uses a Monster Cassette Adapter and a KINIVQ Bluetooth Adapter that allows me to use the Bose speaker system to listen to music from my bluetooth devices (iPod, cellphone, etc.) and to answer and make phone calls. Once the KINIVQ adapter is paired with the bluetooth device, and the cassette adapter is fully inserted into the cassette player, all the functions of the bluetooth devices are available using fewer resources. The total cost of the devices was about $35 but other similar devices may vary in price. Since both the Monster adaper and the KINIVQ adaoter use male input/output wires, I used a female-to-female connector to marry up the two input/output leads. The power lead for the KINIVQ device also has a USB port so you can charge your phone while using the new system. I also suggest that you use a cassette tape head cleaner to clean the heads of the cassette player if it has not been used much in the recent past. This will result in better sound quality.
As part of my project for the use of bluetooth devices and as seen on the attached picture, I hardwired an additional aux power socket (located to the right of the radio) by combining the hot wire from the existing cigarette lighter wiring behind the center panel beze to the hot wire from the new aux port. I then bought a $15 USB (1)/Aux Power (3) device and used the power from the new aux power recepticle to power this new device. This allows for using the aux power system for cellphones, GPS systems, and other devices that are capable ofusing 12 volt systems with an appropriate electrical adapter. This arrangment also allows for keeping the original cup holder door closed to minimize clutter.
The picture shows the Monster cassette adapter in the cassette opening and the KINIVQ bluetooth head located on the upper right side of the radio using velcro. The new USB aux power recepticle is between the passenger seat and the console. Since the wires from the cassette adapter and the KINIVQ device are long, I hid the connector and the remaining wire in the glove box. The system is simple and easy to install and use with mostly hands-free use of the phone. If you have questions, please let me know.
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