Sever, Where are you sourcing 'stepping rings' from? I found the Fuji wide angle lens has a 70mm mount diameter - pretty useless for putting anything on!
I've got a piece of Kodak Wratten IR filter (celluloid, not mounted) so will see what I get. Probably need 1600 ASA though!
I tried it, my gel filter's a No.87C. At 1600ASA in daylight manual mode f2.8, long shutter, I can see IR sources(tungsten lamp) in the viewfinder. I can see the IR emission from a TV remote, straight into the lens.
I don't think the 602 will ever compete with an image intensifier/night sight. However, If you throw a couple of hundred watts of IR at something you will get pics I'm sure.
One problem might be focusing. IR is a longer wavelength than visible light, and the focused plane for lenses, on the ccd, will not be the same. Experiment with manual focussing