Hy glasman, my brake catalog lists 1950 as the last year for the 11/4" fronts with the adjustment wheels on the end, the 1951 to early 54 use a 1" with no adjusters Raybestos WC14497. Is your backing plate equipped with the adjustment slots for the wheel cylinders you removed? If it does, maybe someone replaced the whole front axle with a different one. My catalog crosses 5453781 into WC14481 which is a 13/8"bore cylinder, hope that helps.
