Rocker shaft oil hole.

Down... if you put them up you will have a well lubricated valve cover and need to buy new rocker arms
I bought a 71 police interceptor 440 from a guy in the AF back in 1982. Engine made a lot of noise from the top end. Tore it down and found the rocker shafts were upside down and bone dry. The shaft was deeply scored and blueish in color. Yep, whoever worked on it did not know about Mopar shaft orientation!