I got my radiator fixed today for $35.00 by the superman radiator man Ralph at Bird's Radiator Service in Waxahachie, Texas. Ralph has 30 years experience and can fix "anything". Better for me than paying$400.00 minimum for a new core and then it wouldn't have been original. The problem diagnosed earlier was a broken tank seam and a pinhole in the back of the top tank. Took about 30 minutes of professional help. No hexagonal cores are available now, but you can get new ones for about $1,500 if you wish. Thank all who assisted, and "call Ralph"!!