Storyline: I replaced the spark plug wires amongst other things and found that I was only able to run air through the defrost vents. I understand that it's a common problem snapping that vacuum line and that the blend door defaults to the defrost setting. I'm trying to replace the line which snapped nearly flush with the firewall (engine compartment side). However, it appears that where the line penetrates the firewall, that it actually travels through a clamp or something. I've been racking my brain trying to figure out how to replace it and I'm having no luck. Any help would be appreciated.