Greg I printed up a batch of four pins (as seen below).
I made them a tad larger in OD than OEM, and tad longer than OEM.
Hopefully for a bit more secure fit than OEM.
Anyway ... if you PM your address I'll send them out for you to test. You'd have to supply the hardware (unless in the meantime I find the appropriate stuff in the shop). I realize you aren't going to disassemble your car to check the fit ... but I trust you can eyeball them and see if they will work.
To be honest my GTO is right down in the shop, but I also don't want to take anything apart
So maybe compare these to the one remaining pin you measured to see if you think they will work. I don't have any more old grills lying around.
When it comes to the screws .... big enough to bite, not big enough to split them. Holding them still to install the screws might be sketchy. If too sketchy I could add flats for a wrench.
