Once digging threw the files in the 650's ROM I quickly found the “btmanager” overlays which showed the DUN option proving that it was built in. I then referenced the control to the “btmanager.prc” code and found where it was called. While tracing threw I found a subroutine that did nothing other than “hide” the control. So I just eliminated the two calls to this routine by “NOPing” them.
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