Yes, before i put the adapter npt into the brass fitting a 3/8 nipple came out and it had the 3/8 diameter.

this is the restricted setup I had. This threaded into the 3/8 female bung
that is welded to the top of my tank.

I tossed it !!

this 3/8 nipple has a inside diamiter of .495 the brass tube fits perfectly
into this with a 32nd under 1/2 inch id. Go to a hobby shop and get the (15/32) correct lenths then solder it into this nipple this will drop in and thread into your 3/8 female tank then thread the appropriate adapter to the top. I cannot show the thinwall tubing cause there now in my tank.
Dont forget to cut the bottom of tube to a 45 incase your off on your depth
measurement.

Caveman thanks I will let you know what i find tonight.