How to identify "302" heads???

Thanks for everybody's quick response! Question for George Jets: On the 714 heads is that casting number under the valve cover as well as on the Combustion chamber side? The engine is assembled as a long block, so it would be easier to see that way.

Yes, whether 302, 646, 714 all the same heads, last 3 digits will be there under the valve cover.

20200816_165923.jpg