Brake line fitting size

[69SCSS]

My front disc line going from the prop valve to the T at the frame rail has a crack, and looking to replace it (it's leaking a drip of brake fluid each time I drive). What is the fitting size, 7/16-24? I found a couple replacement brake lines but since I need to keep the line on until I replace it (had to drive without it), I can't really bring it down LOL

My flare kit sucks and I need to replace it, otherwise I'd just fix it... but the line is really old and tweaked, so prob a good idea to replace it completely anyway.
Any help is appreciated.