Fuel pressure line flare nut size?

[bahamasair]

I'm adding an extra inline fuel filter and want to tap into the flare nut where it transitions from the hard line to the rubber line that supply's the original filter. Does anyone know the size, type and pitch of the thread that the flare nut uses? I'd like to order all the adapters I need.
Thanks for any help.

 

[inkpot]

Why? I just cut open an OEM filter with nearly 100,000 miles on it and it was a long way from being loaded up/blocked.

 

[Hornd]

If fuel filter is plugged, then Fuel Sock on Fuel Pump (in tank) is plugged.

 

[bahamasair]

I'm using injector dynamics injectors and they call for a 6 micron filter. I'm going to go by what they say I need incase I have to waranty my $700 injectors.