sb timing cover question

okay here is what i found based on all of the info above(thank you all that responded). all 3 have timing marks on drivers side. 2 are part number 3769966 and circle date shows 77 and 79. these numbers are upside down. the 3rd one is 2981698 and circle has 70 in it and all numbers are right side up. so thanks to all that help me to figure out this deal.