wow, nice work. I am still waiting for my BT stuff from Dell parts. I might try something like that, but include the connector somehow incase I need to swap out the 350 at some point.
Do you have the pin outs for the type a to type b connectors? Im not sure which one is pin 1 on each connector. Maybe it will be easy to tell when I have everything in my hands, Dell parts just shipped my items today.