This explanation of ball joint socket sizes may help.
Back in the 20th century, there were 3 socket sizes for 3 different ball joints.
Let's refer to them as small, medium and large.
We can also use Moog part numbers to distinguish which socket fits each ball joint.
The information provided in the tool catalogs can be confusing.
The tool companies used fractional sizes to describe their sockets. As you will see some companies used 64ths,32nds 16th etc. regarding the dimensions of their sockets.
Moog K704 used from 1960 thru 1972 small ball joint uses the following sockets by Snap On, Mac and Proto.
Snap On S6302A - 1 51/64
Mac SC52- 1 25/32
Proto 6549L- 1 3/4
Moog K772 used from 1973 thru 1976 medium ball joint
Snap On S9365B- 1 59/64
Mac SC29- 1 29/32
Proto 6550- 1 7/8
Moog K778 used on Chrysler Imperials and Dodge trucks large ball joint
Snap On S9479A- 2 3/16
Mac SC30-2 1/8
Proto 6551- 2 1/8
All of these dimensions came from Snap On, Mac and Proto tool catalogs from the 1980's and 90's.
The problem is the tool companies were giving approximate fractional sizes.
You would have to use a digital caliper which read in decimals to get a precise dimension of each socket.
If you were to measure all three sockets listed earlier for the small ball joint, they would all be the same within .001 to .002 inches.
Because of the difficulty of finding Miller brand sockets, they were left out.
All of these made in USA sockets can be found on eBay for reasonable prices.
By the way Snap On still makes the medium size socket and the current price is $128.00.