need help.. lower balljoint

Here is a little more info:

The spindles on my 72 Demon are LBP from a 72 E-Body
Bolt Diameter is .61
Ball joint is attached w/ nuts & bolts

The 4 piston Kelsey Hayes SBP that were on the car before
Bolt Diameter is .52
Bolt actually goes thru the ball joint and threads into the spindle