Removing transmission lines

I have a 1993 ford taurus 3.8L V6 automatic GL. I am replacing my radiator. I am having a terrible time removing the transmission lines from my radiator. I tried to remove the two lines using a flare nut wrench but could not get them off. The lines are hard to reach. Should I replace both lines?

The lines on Fords typically need a disconnect tool, like this:

You slide this around the line and into the fitting to release the line. Most parts stores have these. The metal ones are worth the money.