To get over the tygon issue, yes there are different kinds of tygon, the one that is suited for our needs is the the yellow "special for Gasoline fuel" usage with the words tygon written on the tube itself, there are some other look a like brands which are more transparent than tygon these get hard with time but better than clear vinyl line (prather products) it's also cheaper than tygon but to my likes not good enough, I have tygon fuel line that it been on my plane for 2 years and it's still flexible enough to work with but this is the original tygon, I buy it bulk through my work place. the only place I replace it once a year is the pick up line inside the fuel tank just to keep it as flexible as possible.