I have a V8 4.7L Durango. The local shop recently told me that the low pressure port on the A/C line was leaking slowly, and would not hold an R-134 charge. In looking at my options, would it be possible to replace that section of A/C line? If so, how hard would it be? I'm wondering if any special disconnect tools would be needed, etc...

I have seen several LP A/C lines in Durangos at the junkyard.

 

Most of those ports can be screwed out and replaced or rebuilt. Look at it to confirm.