273 La engine oiling

Well ....
Rocker Shaft Bolt 30 3/8-16

is what it calls for but I will agree with ^^^^^

That is a well known misprint. Sometimes you have to use your head and say "huh?" A grade 5 3/8 bolt is "standard torque" at 30 ft lbs for -16 thread, therefore a 5/16 cannot be.

This is a little hard to read but...... 5/16 grade 5 course thread is 17 ft lbs