Last night I put in the Bluetooth radio. I have decided to change to a physical DPDT switch rather than a multiplexer, since the MUX that I have on hand is a DIP version and is too large to fit into the case properly. (If I were designing a board for this, it would be no problem to use a SMD one, but deadbugging a DIP is way too large).

Next step is the XBee radio, and then we are just about done the hardware portion.