I think you hit the only 2 boxes. The Toy Fair car and the Dwarf signal is all I can remember as well. The only other "1 off" box I can remember is the Lambeir(sp) packaging truck. They are or were the box supplier for Lionel and did a special box for their own truck.
Hello, The only two items Lionel ever put in the "blue" boxes are the two you mentioned. The 1996 Toy Fair car and th eDwarf Signal. The LITTLE rialroad club is coming out with a commemorative car that is also supposed to be in a similar "reverse color scheme".
Chuck
"see3" on Choo Choo Auctions
Thanks for all of your help I was not aware that the ambassador cars were in a blue box They are rare only have seen one that was not in a box. I have a feeling lionel will eventually go to the blus box