Hi Joe,
Sure, I think you could try it with that setup. First, remove the straps that connect your "top" and "bottom" inputs on your speakers. Then, do something like this:
Denon speaker outputs to the "top" of your speaker inputs using speaker cables.
Denon preamp outputs->Carver main in->"bottom" of your speaker inputs using speaker cables.
That's pretty much it to do the bi-amp setup. However, I'd match the levels of the two amplifiers. I'd probably do this before any of the setup stuff above. Just connect the speakers "normally" (i.e., with the straps), set your Denon to play a tone or noise using
REW, and then turn your volume up till it measures, say, 75 dB. Then disconnect that, go Denon->Carver->speakers (still in full range mode on the speakers), and remeasure. Be sure to leave the Denon's volume knob at the same position. Adjust the Carver's volume knob until you measure the same SPL. Like I said, you can use tones at varying frequencies (I'd probably pick 200 Hz and 1kHz as starting points), or you can use pink noise. Go back and forth until you are satisfied that you are going to the same output level from both configs. You may also want to try different volumes and make sure that things stay linear.
Ultimately, you'd want to have identical amplifiers all the way around, but this will work. You can also experiment with the Denon driving the "bottom" and the Carver driving the "top".
Good luck!