Problem with replacement Idler Arm

That is exactly what the one I took out of my car looks like! If I understand correctly, someone prior converted the center link to 73-76 style?

That is what it would appear since that idler arm matches yours. I am very interested in seeing your pictures. Your parts could be off a 73 up and bolted to the original K frame from the sounds of things. The pictures should tell the story when you get them posted.