The " C " Body with Disc (1967 - 1968) Lower Ball Joints are sadly R & R -- only --- (as in rebuild and return)
One of the front end outfits in California opens them up --- puts in New balls and sockets --- and closes them back up....
They have NO "Cores" however; yours or somebody's units would have to be rebuilt....
The drum brake ones DO NOT fit --- they do not go
"around" the 4 - piston caliper......
Yours, Craig.