Here is a photo of the McKaig-Hatch wrenches used in at least 47-55 Advance-Design tool kits (standard through '48, but an accessory from 49-55). A few slides earlier in that album is a photo of a complete tool kit (I do not know if this is a McKaig-Hatch or Vlchek kit).

There was no adjustable wrench in the 47-55 tool kit; and, the plug socket would have matched the size of spark plug for that year (duh).