This may not be much help but I just put together my front clip last weekend on a 47. I think you're referring the two holes next to the headlight that attached to the grill. When I removed it they were not bolts but screws with hex heads...3/8 maybe. I bought a bolt kits from classic parts for the front clip and it came with these same screws and they worked nicely.
Hope this helps.
-Nate
