Filter housing thread size?

[Austin86250]

What size threads are circled in red for my 6.9 and is it the same for the 7.3? as I may swap it in the future
I’m going to put in a carter 4070 fuel pump

 

[Nero]

1/4 pipe thread, should be the same.

 

[Jesus Freak]

I have a strong "feeling" that it's NPT, but that's pure emotion. Wait until you get a confirmation. And I also "feel" that the 7.3 is different, Nero might be right, but it just seems like I've seen different. And I also know that most all the electric fuel pump guys are into the Holley red or black, but I'm a mechanical fuel pump guy right now.