Probably a Scott McCulloch. Scott Atwater became Western Auto outboard supplier in late
1950s about time McCulloch acquired Scott Atwater and name evolved by stages into
McCulloch. After 1964 models West Bend/Chrysler supplied outboards to Western Auto
and other retailers.
Scott McCulloch offered a 3.6 West Bend/Chrysler offered a 3.5 under the Wizard label
according to my reference source.
Hope this is helpful