Tire Size for 5.5 small bolt rally wheels on 64 Valiant 200

Is the wheel well the same from Dart to Valiant those years? I think the Valiant is different is it not? I cannot remember.
i've never had the two side by side, although having worked under both, i think the valiant is a a little more narrow toward the top. but i don't see a 245 being a problem to fit if you're not super low and it's got something close to factory rear end width (you're fitting a 9" down the line, no?)