1970 dart right lower ball joint question

Check out the chart on Big Block Dart

http://www.bigblockdart.com/techpages/techindex.shtml

http://www.bigblockdart.com/techpages/moognumbers.shtml

K7021 is for the older cars with the 4 piston Kelsey discs

You likely have the 73/ later single piston, "somebody converted"

Yet another thing you need to be aware of is whether you have a "big spline" steering box. There are 4 pieces need to "go together"

The steering box .......spline size

pitman arm must fit the spline

and the center link and the idler arm must match.

The 73/ later "4 pieces' are different than the "72 and earlier" and has nothing to do with other parts, that is you can have later parts in an earlier car, and vice versa.

Here:

http://www.forabodiesonly.com/mopar/showthread.php?t=236925

Post no 2. The earlier pitman / idler has the stud nuts on TOP, and the later has the nuts on the bottom.

Also affected by the type of disk brakes you have is the upper a arms and ball joints. You could have 73 disk brake A arms and the "larger" ball joints or you may have the earlier smaller ones with bushings in the tapered studs, but the latter is rare