1970 duster heater box

Same hose kit comes from DMT and other vendors. In a perfect world the thick wall adapter would be formed of hard plastic or something that could have a clearance flat cut in it. As it is we do what we must to make it work. I didn't use the thin wall adapter. I might have inverted a bit of that hose inside its self ( I forget ). My zip ties are laced one under the other. The hoses aren't going anywhere.