Intake Manifold Heater Hose Connection

I went through this on my 67 Dart. I have an Edelbrock air gap intake also and I just screwed 1/2" hose fitting in the intake, slipped on the 5/8" hose and tightened the hose clamp down and have never seen a drop come out of it. I did a lot of searching but could never find a 5/8" hose fitting to fit that intake.