I have done a fair amount of night time surveillance using some of the same gear, though we still don't have a surveillance van. Maybe next FY. I am away from the sneaky side and back doing grunt patrol work, but NVDs are still quite useful during our night shift roatations for catching burglars, running perimeter containment and other various attempts at being sneaky, and I am looking forward to getting back to nights at the end the month after a long, very hot summer on day shift.
In my experience, I find that using a PVS-14 with a 3X magnifier will allow you to read a license plate at about 50 yards or so, more if there is decent ambient light.
A SF M900 turbohead with an IR filter will illuminate the LP just fine if the light isn't good enough, though one has "play" the beam around a bit to avoid getting glare from the reflective elements in the plates. The Turbo head IR filter works on the standard "cop issue everywhere" Streamlight SL-20. Again, this seems to work out to about 50 yards.
I have also used PEQ-2As or PAC-4Cs with the same effect, but you typically get a bit more range, sometimes as far out as 100 yards. The nice thing about PEQs and PACs is that your agency can get them free through the 1033 Program, and there usually seem to be a few available, somewhere these days, and even a PEQ or PAC that is unservicable for its intended use (weapons aiming) because the beam won't adjust for windage and elevation or the mounts are broken may oftentimes be just fine for handheld illumination purposes during surveillance. Order about 5 each from a couple different lots, and you should get two or three that will work (at least in my experience with surplus illuminators from DRMO). If this stuff works fine with PVS-7Bs and PVS-14s, which is most of what I have used since I got nicer stuff to replace the ancient PVS-5s and PVS-4s we were using, then it should work fine with your CCTV stuff, as long as the II tubes for those systems have decent resolution.
Good luck and happy hunting.