69 barracuda dash to firewall bolts

This car has been totally rebuilt and during that rebuild, I made the mistake of having my windshield installed prior to attaching the dash to the firewall. I now must have the windshield removed and put 5 bolts thru the dash and into the firewall. Since I will be doing this at an auto glass shop, I need to know what size those bolts are so I do not delay their business. Would anyone know what they are and what kind? I.E., 7/16ths threaded coarse or maybe sheet metal screws. I'm the one who disassembled this car but it's been to long, I can't remember.