Fueling & Injection - Factory fuel line T block thread size question...

On my 98 T/A I have the returnless style fuel system. The main supply line goes into the fuel filter, out of the filter, and into an aluminum T block thingy. On one side of the T block the line comes out and goes up to the fuel rails. The other line goes back to the tank, and to the regulator. I am converting my fuel rails to a return style rail from a 97-98 corvette with the regulator in the rail so I don't need the return line that comes from the T block. Does anyone know what size/threads are of the line that threads into it for the return? I just want to get some sort of pipe plug to block it off and use the T block as a pass through. Thanks for any info, Paul M

BUMP!

Going to be doing this rail conversion this weekend and would still like to know if anyone out there knows the size of the threads. I figured maybe I am not describing it properly so here is the best picture that I can find. I know that the 2 spupply lines are 3/8 steel and the return line is 5/16 steel. Maybe the fitting is some sort of 5/16 inverted flare?

The correct parts you need to plug that T-block are:

Russel Part # 648070 (14mm x 1.5 O-ring to -6AN)
-6AN Cap (I used Summit Racing part number SUM-220640N)

This picture is the wrong size fitting (16mm), but the correct part is damn near identical:

http://i305.photobucket.com/albums/nn227/meentss02/FuelSystem026.jpg

There is also a lot of good information in this thread:

http://www.ls1tech.com/forums/fueling-injection/1084807-how-convert-return-style-fuel-system-pics.html

MeentSS02 thank you so much for that post. That is exactly what I have been looking for. I was hoping that I could just find a pipe plug to use, but the combination that you gave should be more than adequate for what I need. Thanks again!

MeentSS02 thank you so much for that post. That is exactly what I have been looking for. I was hoping that I could just find a pipe plug to use, but the combination that you gave should be more than adequate for what I need. Thanks again!

No problem...I had a hard time finding my old post when I searched for it, so hopefully having it in a couple places will help some people out in the future.