I’m in the process of replacing the transmission cooler line assembly on my 2009 F-150 with 4R75E 4 speed transmission. I have the new lines in and everything buttoned up leading back to the transmission. I’m having a heck of a time getting both flared fittings to thread into the transmission. I can get one to thread in just fine, but will try the other and have trouble guiding it in straight and seems like I may cross thread it. I have tried screwing in one before the other and vice versa, and with plenty of play with other mounting points along the assembly being loose. Still struggling to get the opposite fitting to screw into the transmission straight and flush. Any help is appreciated.

 

Finally was able to wiggle things around enough to line it up and thread it in flush!

 

Glad you got it done.
I was just going to suggest. Cut the end off the old line, file the beginning threads down a bit and use that as a thread restorer.