I checked the rocker arms for any offset from center of the oil grooves, and found the grooves to be centered. The block has the 3/16" oil line under the side cover, so who knows why "Wally" put that specialty bolt in there, or where he was even able to find one.

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