thanks for the insite guys. How exactly do you figure out if it is a # matching engine? Should vin stamped on front of engine by engine code match vin of car on the dash? I was doing some research on yearones website earlier and they didn't show a WN block till 73 is why I was asking. But the PHS documents I got shows WN as late production engine with 45 degree valve seat angle and WK for early with 30 degree valve seat angle. My PHS shows a shipping date of 12/04/68 but would guess was built just prior to that date.