Welcome to the Team John!
This will be one of many parts you will have to replace most likely. I recommend attempting to find an Assembly manual to look at ther exploded view diagram showing all of the parts and glue or gasket material needed. Another source is the Fisher Body Service manual as it covers Air Conditioning in a separate chapter, or even an old Chilton's or Motor's Service repair manual purchased on line.
One advantage of buying a Chilton's or Motor's Service repair manual is that they written for the amateur mechanic versus the trained service tech that the factory books are written to provide a reference to.