Was getting read to reinstall my bevel gear assembly, and noticed that there are guide pins in each of the main bearing caps that retain the cages in place and keep them from spinning. (red circles, go in green circle):
 

One of the guide pins is just about completely flush with the cap!  What would cause this?  
 

On the cage that was used with this cap, there is a dimple where that pin was.  I don't see any rubbing around it, so I am guessing maybe they set the backlash without tightening down the bearing cap, and it spun a little?  If it had spun during operation I would think it would look different.  Anyone have any ideas on what would do this, or seen this before?
 

I assume this is something I should fix.  Shouldn't be too hard to grind out the weld on the cap and replace the pin then weld it back up.

Yea that pin should be down in the groove, somebody installed it wrong before and pushed the pin up in the cap. Tap the pin back out so it protrudes out further when assembling, after you got the cap snug and backlash set tap the those pins down so they stay down in the groove all the way.

Think I accidently deleted the thread when I tried to edit it, whoops.

I ended up replacing the pin. The pin is made out of hardened steel, and it's supposed to be beveled at the tip. The bad pin was missing the bevel so it almost looks like it was worn or cut down.