Someone has been reading up on the Bullitt. That's the only place where I've seen the term "Euro Flange" used. In any event, these are the same wheels as the "optional 18" polished" wheels that quite a few people have. Only difference is, the Bullitt ones are painted an Argent color. These wheels are only 8.5" wide, so you're not going to get the fat tire you're looking for. You need a 10" wheel back there with something like a 305/40/18 to get what you're looking for.
Oh, that is what I have, the 18" factory polished, I assume they are 8.5" wide rim? If that is the case, I could buy just two rims, the 18" with a 10" width, run the 305 tire in the back and just have the rims painted the argent color. Make sense? I can just leave the stock fronts in place.