Who has the rundown on the evolution of the LA series engine?

The heads on this engine didn’t have the casting numbers visible. It has been awhile since I’ve paid attention to casting numbers on heads so i am out of practice.
I looked at another set of heads I had in the shed. FABO member @mopowers Made me a deal on them a couple of years back
They have the casting numbers on the other side facing the valley. #308. The heads on this engine might actually be the same castings.