That's what I'd do. Get yourself a 1/2" x 1/4" reducing coupling and solder it on to the CFC. That will give you a 5/8" OD on the CFC for your 1/2" tubing to stretch over. The other way to do it is to put a 1" long piece of 3/8" ID hose over the CFC, then put some 1/2" ID hose over that. Clamp.