What is the thread of the cooler line fitting out of the radiator line at the top of the radiator that returns to the transmission. It's not mpt. I was looking for a barbed hose fitting.

Can I just cut the line there, hose clamp in the lines, after flaring the line, and call it a day?

What kind of pressure does it have?

 

It's low pressure, so yeah, you can just use hose clamps and such. Flaring the end a bit to prevent it from blowing off is pretty much a requirement.