Rant about Trans Cooler Lines

[Accelo]

Do you have the bubble-style fitting on the transmission? I am assuming so.
You can retrofit the fitting back to the flared ones if you like.
Inline tube may have them?
I would recommend it as they are much easier to deal with. Just be careful as GM used both 5/16 and 3/8" lines. It depends on the GVW and year.
Another option is junkyard lines. I have even used the 5/16" compression fittings to connect two lines. I hide the fittings under the engine.