AN fitting threading tool?

[J-440]

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[67 455 Bird ragtop]

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This might help ...

Dash No.----Tubing Size----Thread
-2---------------1/8--------------5/16-24UNJF-3A
-3---------------3/16------------3/8-24UNJF-3A
-4---------------1/4--------------7/16-20UNJF-3A
-5---------------5/16------------1/2-20UNJF-3A
-6---------------3/8--------------9/16-18UNJF-3A
-8---------------1/2--------------3/4-16UNJF-3A
-10--------------5/8-------------7/8-14UNJF-3A
-12--------------3/4-------------1-1/16-12UNJ-3A
-16--------------1----------------1-5/16-12UNJ-3A
-20--------------1-1/4----------1-5/8-12UNJ-3A
-24--------------1-1/2----------1-7/8-12UNJ-3A
-28--------------1-3/4----------2-1/4-12UNJ-3A
-32--------------2----------------2-1/2-12UNJ-3A
-40--------------2-1/2----------3-12UNJ-3A
-48--------------3----------------3-1/2-12UNJ-3A