340 adjustable LOCKING rocker arm kit

The problem is, PRW shows TWO different part numbers. One is clearly advertised as 7/16 the other is not so clear. There's no reason for two different part numbers in the same size, so it's gotta be a typo. One is 3/8 and the other is 7/16. You're probably gonna have to call someone at PRW that will actually WALK out in the warehouse and LOOK at the part.
Man, the Good Ole Days of Phone Calls AND Customer Service! Ahhh, brings back memories...