I somewhat misinterpreted what the OP asked or I would have told him the same. But, oddly enough, thanks to the lack of a "Tune" or "Analyze" function, you can't sit on a CC and obtain both the raw audio from the discriminator and the PC/IF data. Not sure why one would want to -- except to maybe compare how well the scanner is natively decoding the control channel data vs how well UT [or some other trunking program using discriminator audio] can decode it. It'd be interesting to be able to have two instances of UT running, one monitoring a CC using the PC/IF data and one using discriminator audio -- but both coming from the same scanner.To get voice audio and control data at the same time requires two receivers. No amount of firmware hacking will change that. Most consumer scanners don't have dual VCO tuners.
You might look at GNU radio with a USRP but you're still tethered to a PC.