You do realize that your switcher only has composite video for the Preview monitor, so you are not going to be able to be digital everywhere. And are you actually using the DV Program output?
Without knowing what cameras and monitors are involved, it is difficult to give a specific answer.
The simplest approach would be to find monitors with looping DV inputs, go from the camera into the monitor and loop out into the switcher inputs. That way you're monitoring the actual signal going to the switcher. If the monitor doesn't have loop through on the DV input, then you could use a DV distribution amp to split the camera signal to the monitor and switcher.
If you already have, or plan to procure, monitors that don't have DV inputs, then you need to look at how to get the DV signal to your monitors as some some other signal format. It may be that your cameras support a composite video or S-Video output simultaneously with the DV output, so you could run that to the monitor. If not, you may need to convert the DV camera signal to another format for the monitor, perhaps even having to DA the DV with one output feeding the switcher input and another DA output feeding a converter that then feeds the monitor.
