When we ran a full service chassis fab/turn-key hot rod shop a number of years ago, it was always useful to have threaded things around to weld into the frame for some kind of mount, etc.
Here’s a list of all our threaded things for your reference:
Ball Joint Spacer, 1" OD x 5/8" ID x 0.348" Thick
Product Details
Brand: Welder Series
MPN: K772S
Country/Region of Manufacture: Canada
Thickness: 0.348"
Diameter: 1"
Hole size: 5/8"
If you’re using Chrysler K772 ball joints in your Mustang II lower control arms, this spacer is necessary so that the taper in the spindle will engage the taper on the ball joint before the ball joint nut runs out of thread.