If you have a local NAPA Auomotive Parts Store they should be able to help you.
Check the NGK cross reference for the Wisconsin engine. Probably an AB-6 will work. I used to have a chart for those old industrial plugs but it went away and is hiding.
Current replacement is an Autolite 3076 or ACDelco C75 or Champion W14
This is a 7/8 in (22mm) x 5/8 in. reach plug.
Thanks everyone for you assistance in crossing these plugs.
Pete, Your actual description sounds like them!
Again, much thanks!
Greg
I thought "almost all" Wisconsin engines had Champion D-16's listed for the correct plug. Isn't a W-14 bigger?