Starter ?

Once in a while, when I turn the key to start mt '87 LS the starter sounds like it's spinning free. I turn the key off, then try again and it works. Sound like the drive, or the solenoid? What do you guys think?
I do have an extra starter with a broken nose part that I can get whichever piece it is from.

Sounds Like You Got A Solenoid Problem. Try On The Old Solenoid That Should Fix The Problem.