Flange or NPT Fittings on Gas Tank?

[Death Dodger]

I recently got a "Tanks, Inc" gas tank of Ebay for my 1940 Dodge. It's for a 41 to 48 but fits the '40 great. The sending unit hole was in the perfect position, filler neck mounted right up and fit great (I feared I might have to cut and weld...). The shape is a little squarer than then original, but no biggie.

The fitting for the fuel pick up on the new tank looks to be 3/8" but I can't tell if it's flare or NPT. It has the "dome" shaped seat on the back of it like a flare fitting but nothing seems to fit it. 3/8" NPT gets two turns by hand in and feels like it's supposed to fit.

The stock fuel line has a flare fitting on it, either 1/4 or 5/16".

Can someone please tell me if gas tanks usually come with flare or NPT and what I might be doing wrong?

PS. the only other issue I had mounting the gas tank is the straps. The new tank is slightly smaller so the original straps are too lose. It came with straps but they don't have the correct fittings on them. It should be easy enough to cut the fittings off the ends of the original strap and rivet them onto either the new straps or back onto the (shortened) original ones.

Thank you.

[54Illinois]

You could use heavy gauge band iron for the straps.

[Frank Elder]

I believe Mr. Flanagan welded the old strap and new strap together to make them work.....maybe he'll chime in.

[TodFitch]

Fuel outlet on my '33s tank is NPT. I understand that in the '46-'48 time frame they used a flare tube with a ferrule. You are in the middle year wise so it is a toss up as to what they may have done.

[Jerry Roberts]

My 1941 truck fuel tank outlet takes the same fitting used on a brake line . ( flared )

[Oldguy48]

I think I'd put in a call to "Tanks, Inc." and find out exactly what it should be. Better to make a phone call than to possibly booger up the threads.