I recently pulled the fuel tank out of my 1975 280Z to have it cleaned and so I could work on reducing the smell of gas in the cabin.  I'd love to replace the 17mm (5/8") vent hose that connects from the tank to the vapor reservoir and the 17mm hose that connects the filler to the vapor reservoir, but I can't seem to find these parts.  I question whether or not the existing hoses are presenting much of a barrier to gas vapors.  Anyway, I was thinking about replacing them with 5/8" fuel hose; how