Auto Parts: disconnecting ac line from firewall, ac evaporator unit, ac lines

Question
Hi.....not sure if you can help.  I need to replace the ac evaporator unit in dodge ram.  In order to do that I have to disconnect the ac lines from the firewall.  I have removed 2, but 1 will not budge for me.  I have tried an ac spring compression tool, but it will not budge.  Any suggestions?  Thanks, Mac

Answer
    I don't know what year your truck is.  I have not worked on Dodge air conditioning for some time.  They used to have a unit-type expansion valve that was bolted to the evaporator at the firewall, and then the hoses terminated in a block that bolted to that.  The hoses were held on with a single bolt, and then the valve with two smaller bolts.  If yours is held on with spring couplers and the tool didn't work, it may be the wrong size.  Ford uses four sizes for A/C, GM uses some different ones on some of their fittings.  And, there should only be two hoses going to the evaporator, one in and one out.  If I knew the year, I might be able to help better.