I've removed the front subframe to have it cleaned up. Noticed this tab thing and have no idea what's supposed to go here.

I've found that it is most likely #20 in this diagram: https://www.tpocr.com/67-72fbfrtsuspenipc.html

Is there a bumper that goes here? Right now I just have a bolt. Any picks of what does actually go here?

This discussion may help: Bracket. What's it for?

Thanks for the link, Jim.

So its a bracket to be used for a bumper if there isn't one on the LCA. A bumper on the LCA is preferable. The piece i removed from that bracket is supposed to be there? I assumed it was simply a bolt and metal piece left over from a worn out bumper so I removed it. I guess I'll clean them up and put them back in the bracket then.

What you have on the frame is correct as is. Clean it up and put it back on assuming you want to keep it stock.

I actually think it was an engineering screw up during the design phase. I think one engineer was designing a bumper on the LCA and another engineer was designing a bumper for the LCA but on the frame. When these two engineers finally talked, one of the bumpers had to be removed so the frame one lost out. If they had talked beforehand, all they would have done is welded a metal bracket on the frame that was a solid piece. Just a theory on my part.

My theory goes...camaros were designed/ produced to use the bumper on the frame and when Pontiac engineers designed it they decided the bumper should go on the LCA. The 67s maros I've seen didn't have the holes in the LCA for the bumpers.
Just what I've seen.