If the distributor is Delco 1112388, that is the distributor for 54 with manual transmission. Uses a steel gear. 1112396 is for 54 automatic. Uses a cast iron gear. Both use what Delco Remy specified as a “I” cam angle range which was 38-45 degrees of dwell. You were pretty close at 37.4. The 1112403 was original equipment for 55 and up, but the service replacement unit for the earlier models. Those model distributors use a dwell of 28-35 degrees. The 55 and up cam for the points is different from the cam used in the 54 and earlier distributors.
