Probably NOT the much desired "small head" Williams (and others) box wrench that will actually clear the narrow space the GAV is located.
See
https://www.fordgarage.com/pages/gavwrench.htm for a pix.
Any of the Williams, Armstrong, or others "industrial wrenches" are of course collectable in their own right.
I've been passionate on "Engineers wrenches" for a while now. One remembers the "racks" in the Power Plant Machine shop from 1/4" all the way up to about 5"
There was a 7" over in the corner for adjusting the pulverizer springs - but it didn't have a space on the rack.
Joe K