Find a wrench which better fits in the tight spots on the middle bolts, or grind or heat and bend the wrench that you already have.
Loosen all of the bolts, then tighten each one to less than final torque specification (10 ft-lbs).
Proceed to tightening them to final specifications (20 ft lbs center bolts, 30 ft-lbs outer bolts).

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission