A common failure on these GM GTO A/C systems is the fitting that connects the evaporator tube to the A/C dryer. Once the factory fitting breaks, the entire tube assembly typically needs to be replaced - and it is extremely difficult to route that particular hard line.
 
StanceCo. offers this fitting as a simple replacement solution, allowing you to repair the broken connection without replacing the complete evaporator tube.
Female to Hardline Adapter
Replaces the commonly broken factory fitting
Designed to repair GM tube #92209645
Allows you to reuse the existing evaporator tube
A cost-effective alternative to replacing the complete tube assembly
 
If the factory fitting has broken off, this is the fitting you need to get the connection sealed back up and your A/C system back together.