Home › Forum › Ask A Member › 1955 Evinrude 7518 Welch Plugs › Reply To: 1955 Evinrude 7518 Welch Plugs
https://www.marineengine.com/parts/johnson-evinrude-parts.php?year=1958&hp=7.5&model=AD-12&manufacturer=Johnson§ion=POWERHEAD+GROUP
306442 is the part number…. Pretty sure this is what you are looking for.