SInce I am kinda new to the modeling hobby, let me just add a few observations from real life experiences with iraqi armor.
Having served during Desert Shield/Desert Storm, and Operation Southern Watch, I have had the "priviledge" to see these seriously overmatched armor pieces up close and personal.
Minus the multitude of bullet holes from the A-10 Warthogs, the charred and burn marks, and the mounds of rust on even the abandoned tanks, they are a sandy, desert brown color. Some of the areas on the Iraqi armor that I saw up close had some hastily patched and repainted portions. They used a light grey primer underneath. Some pieces of the armor, specifically the BMPs had various battle adournments, much like American Aircraft (i.e. planes shot down types of things). The interiors of the Iraqi armor was a light greyish green color.
Keep in mind, it's important to realize, in battle, most divisions will scrounge what ever they can get their hands on to make expedient repairs. I saw a tank that used a big rig grill to replace ventilation grates.
You also need to decide on what division you are building, as the "basic army" tanks are less updated, more dilapedated, and certainly less impressive looking than say a Republican Guard tank, that is better taken care of, has newer parts, and is generally more resilent than its cheaper brother cast offs.
Most generally, my experience with Iraqi armor has been of the Regular Army Type, less maintained, and more of a mish mash of scrounged parts. Again I reference a tank that used chopped up crowbar pieces for pins on a track.
The BMPs were actually in better shape than the tanks, and looked more resilent on the battlefield unfortunately....
I know this is probably more than what you wanted to know, but if you are building a diorama, and wanted a "no holds barred" evaluation, it may be of interest....