-6 - 3/8" npt?

["Daryl Smith" <drlsmith@telus.net>]

As above, I am trying to go from a 3/8" NPT thread on the end of my fuel rail
to a 5/16" or fuel line. Can't seem to find the correct adapter without a 2
step process (3 pieces).

So, My question is : Is -6 AN the same thread as 3/8" pipe thread?

This type of thing seems to be beyond all the parts counter guys.

Thanks,
Daryl