1968 buick lesabre radiator swap help

Hi, I have a 68 buick lesabre 400 with a 5.7L 350 in it. I have a cross threaded radiator line for the transmission fluid. And it was leaking for about a year just kept adding trans fluid to keep ahead of the leaking. So I tried to rethread it and it failed and I am sick of it leaking so now I have a bought a brand new radiator should be here tomorrow.

My question is, How do I make sure that when replacing the radiator, that the same line doesent re crossthread again? Do i need a new trans fluid line if the threads got funky? I am not a mechanic but a do it yourselfer. I Just would like any tips or considerations I should pay attention to as I dive into unfamiliar territory, and Im kind of wondering if i need to replace that trans line that goes to the radiator because of possible crossthreading and want to fix it right this time.

any sugestions or considerations on anything I should look for?
this is my first radiator swap.

thankyou!