Anyone know what size threads this has? It's going on a 76 1500 inline 6. I changed my distributor and my screw is MIA. It's the 5/16 headed bolt?....fische calls it a screw. Anyway it's part # 68554 but I can't find it anywhere. It's the screw/bolt that holds the cover on the distributor pulley. I want to buy one quick because once it's paid for I'll find it, LOL !!!!