I have few questions if you don't mind. Did you have to have a mini tub to clear those tires? My notch is very similar to yours. I am looking to squeeze a 335 in there if I can. Looks like you may have another 3/4" between the frame and the tires. Did you narrow your rear end to get the rims close. I know with those XXR's the offset is very limited. I too am looking for a cheap route but I may be stuck with CCW's at this point to get max out of my frame notch.
During a hard turn with one side or the other loaded, the tire will kiss the wheel well but thats only during a harsh corner and not enough to hear it or cause damage on the tire. The only way I know its rubbing is because I can see the paint on the inner wheel well. Keep in mind, I have a Ford 9" with aftermarket brakes and total width is about 3 /8" wider rotor to rotor than a stock rear with drums.
Also to answer some earlier questions I did do a metal mini tub, it wasn't pre made tubs I hand made them from sheet metal. I wanted to be able to lower the car with the big tires so the mini tub was necessary.