Biggest Tire In Stock Wheel Well?

i have a 68 Dodge Dart that im swapping a 8.75 into and would like to know the biggest tire while not rubbing in stock wheel wells. i have XHD V8 springs on it. i want to run a 29" or 30" by like 10" on a 15x9" rim... possible?

the reason for the height is that im running 3.91's and its a daily driver.