[Mark McLeod]

I used to control those from a PC via a bluetooth RS-232 adaptor through the programming port. No reason to leave the PC on the robot if you go Ryan's route. The adaptor you found or the cheaper TI/Luminary Micro module should serve the same purpose.

You can run the 2004 RC without the OI as well, by setting the team number to zero.
This may have been dependent on the Master code version, but that's easily checked and corrected.
Basically it'll always have the autonomous mode flag set, but your code doesn't have to pay any attention to it.
The lack of OI inputs don't matter if you control it from a PC, and the RC code works with the serial programming port just fine so you can accept controls that way without a problem.

If you do it this way you'll need to devise a fail safe way to disable the robot when it inevitably runs amuck during testing...

I don't know an easy way to replace the tether/radio with WiFi.