What width rear end for Duster Street Strip stance?
Fo-sure it’s mini tubbed.
Stance = The offset in height of the rear and and front end vs each other & against the stock ride height.
That red Duster looks as if it possibly has a 1 inch over bend on the rear springs with a slight upward height adjustment up front with what look like taller front tires with just enough to give the front enough height clearance for the tire with similar fender to tire distance.
Visit the wheel and tire combo thread (A sticky I think) to see what others have done to fit in the wider rear tires.
Below is my ‘71 Duster w/E- body S/S springs and 275/60/15’s and the wrong offset. I can’t remember exactly what the 8-1/2 wheels had for an off set, but the back spacing is IIRC, 3-1/2 or more inches. There typical wheels. From a Ford or a Chevy I forget.