I don't think it will fit. With 4.5 inches backspacing the biggest I have heard of fitting are 235s on a '67. I don't think that rim will even fit unless it has lots of offset. 5'' backspacing is about maximum from all that I know. You should take the car to an NTB or something, their guys measure tires all day and would better be able to help you fit the biggest meats under there.