transmission cooler lines

Hi,

So i have this reoccurring problem with the dart every year. The Dart came with a 904 and a transmission cooler. Steel lines from the tranny to rubber lines that ran to the cooler. I have changed transmissions and put a new cooler in. I have the same steel lines from the tranny. Where steel line connects to the (3 year old) rubber cooler lines, I have a leak every year.
The steel line has a flare on it, the rubber goes over it with a hose clamp. Last year i just cut the hose and slid it on further and it worked.
I could probably do that again this year. But before I do, is this how the connection is supposed to be? that is how it was when I bought it (my first old car). Also i thought that the new cooler came with the hose and hose clamps.

Is there a better way to do this so that I don't have to do it ever year?!

Also, how much pressure runs through the cooler lines?

Thanks,

Steve