[Farmall] 1925 M/D 10-20

[CDHORN at aol.com]

I would use "liquid wrench" instead of WD-40. And yes, you can twist the  
plug off at the neck (I've done it), but then what have you got to lose?   The 
spark plug will have to come out eventually.  Mine came out at the  machine shop 
when I had the head redone.
 
Clark
F-20