Need your help on: Night Vision Devices

[B.T.]

There is a great chance, that during my next FtF-session there will be a bigger firefight, involving at least three different groups of enemies. This battle will take place in a ruined village. The PCs are sitting in an abondened warehouse, about three floors/storeys high, at the edge of the village. At least one of the enemy groups will be in an open environment. Right now, it is about 7 p.m., nightset will be at 10:30 p.m. This will supposingly be the time, when the fighting starts.
Chances are high, that several units involved will use night vision devices. Some questions occured, I really don't know the answers, and your help would be appreciated.

1. One of the PCs uses an AN/PEQ-2. If one of the enemy soldiers uses IR-Goggles, is it easier to fire at the PC with the LAD? If, how could that be handled? Making the roll for the enemy one difficulty level easier?
2. Several guys use IR-Goggles, or starlight scopes, one person is equipped with a x25 image intensifier. How do the different devices react to sudden bright light? (Most soldiers involved (friend and foe alike) don't have any vision device. Several people have a grenade launcher with them and will certainly fire some ILLUM grenades.) If a user of a night vision device spots an area, that is illuminated by a 40mm ILLUM grenade, will the user of IR-Goggles/starlight scope/image intensifier temporarily be blinded?
3. What about Thermal Sights on a tank? There will be no tank with Thermal Sights involved in this fight, but nonetheless: Do Thermal Sights have any benefit for their user during daylight (e.g. spotting a heat source like an enmy tank behind a thin brick wall)? Reason for this question: I have read about several incidents during the Gulf War, where U.S. tankers spotted enemy tanks behind dunes. This did happen because of the Thermal Sights, right?
4. How much detail can one see, using those aforementioned vision devices? Is it possible to spot the differences in different camouflage uniforms or individual faces?

I use (slightly expanded) Ver.2.2 rules. I know, that the soldier with the AN/PEQ-2 needs IR-Goggles himself. I use the ”Tactical Visibility“ rules from the BYB, p. 223. The background light level is 2 (Very early waxing crescent, new moon was two nights ago. During the night, clouds will build up, so the starlight is somewhat muted/subdued.).