Did you check the mounts for the lower control arm?

It is common for the mounting tube for the LCA stud to break loose in the K frame.

Did you replace the Strut Rod Bushings?

I didn't see it on the list but you may have considered it part of the LCA bushings.

How are the frame rails and inner fenders? Our old beasts frame rails like to rust out especially under the battery and under the floorboards.
Look for cracks in the inner fenders, a sign of too much body flex because of frame rail failure.

Hope it helps.