Hello all, new member here. First, I must admit, I don't know anything about k5's at all, so I figured you guys could help me out. I need help identifying an axle that has been sitting in my garage for a few years now. My friend wanted to install this axle on his K5 but sold it years ago. All I know is that he called it a GM 12-bolt. I snapped a few pics- Any idea what the numbers mean? In the last pic the numbers look like "3896839". I have no idea what's inside, never opened it up, but I could if it'll help. I tried searching the internet but all I could find was a different looking 12-bolt. Any help would be appreciated!!