Steering Box Universal Coupling Sizes

So I need a steering coupling from a manual....got any or know where I can get them?

The parts manual lists the coupling for darts, coronets, chargers, & monacos as 2585335 (power) & 2585334 (manual)

Ebay has the replacement coupling for sale in the NOS box & lists it to fit all models without distinguishing between type steering box & says that both above part numbers are interchangeable:

http://cgi.ebay.com/ebaymotors/NOS-...tZVintageQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Consequently something can't be right about the facts..............