koondawg_74 roadrunner

I have some heads that I pulled off of a 318. I compared them to 74 318 heads and the valves are larger. Under the valve cover of the first one had the numbers 2658920-3 and 10316. On the other side of the head there is a big X on one side and a 3 on the other. On the second head, there is a AAWJ, a 380(possibly 360?), a 123, 1063, and 36715873. On the back side of the head it says 3671587-3. Are these "X" heads since the one has the big X? These both look identical but Id think they would both have X's. Any help would be appreciated! Thanks!

mr340

3671587 1980-76 360 5.9


2658920 1975-67 318 5.2


2658920