tranny cooler lines out of copper?

im probably gonna get flamed for this one here, but what the hell...as i was under my car last night trying to install a set of factory prebent lines for a stock car that has been heavily modified, they dont fit worth a damn. tried bending it by hand a little to tweak it and i went to far and it collapsed a little. oops. to hell with it i said, why cant i use copper line? its a little softer and easier to work with, and would look neat (to me) under there, polish it out then clear coat it. i mean, copper has been used for high pressure steam applications for decades, why the heck cant it work for measly tranny cooler lines?

can i do this?? get a roll of 5/16 copper and bend it out of that? or am i nuts and this is dangerous?

talk some sense into me guys, im just thinking out loud here....