64 Dart GT Slant 6 Convert to 4 speed manual

I was looking at 3 different slant 6 bellhousings for sale on ebay. They do not match the numbers 2463025, 2463027, and 2468431 which is recommended by the slantsix.org article. However, the listing indicates that it is for a 1964 A body. 1964-66 Dodge Slant Six 6 Alm Bell Housing Stick 2468481-1 Mopar Plymouth w/Fork | eBay

Could this be a typo on slantsix.org?

4 Speed Transmissions transmission