I think I will try the wire nuts. Even though the existing soldering looks bad, the connections do work (I turned the grinder on once). If there is a problem using the wire nuts, I can always then solder. Thanks.
Maybe you folks can give me some advice. I bought a 1944 Sears Craftsman bench grinder at a garage sale for $30. After reading the many posts on GJ about replacing the two-pronged cord with a grounded three-pronged plug, I decided to look into having that done. No shop or repairman near me was...