ID of 1980 Scout for Dana 300

[FLY4SCOUT@domain.elided]

       My IH loving dad thinks he's found a 1980 scout in a junk yard.  The
ID plates have been painted over, and I'm trying to give him things to look
for to be sure it really is a 1980 model. (The junk yard thinks it's a 1979)
 I want the Dana 300 if it really is a 1980 model.  What things can he look
for? The only two things I can think of are   1.  Square head lights   and
  2. Speedo cable comes out of the passenger side of the Dana 300 instead of
the drivers side of the Dana 20.   Is there any other way to tell?  Thank you
for any info!