Regarding fuel lines. I found some really nice gasoline-safe silicone line at McMaster-Carr. It's expensive but it's as flexible as the stuff we use for glow and it is indeed gasoline proof. I put a piece in a glass jar with some gas/oil mix I had and let it sit there for months. I shook it up every once in a while and it's just fine. I have some in one of my gassers without any problems. But it's about $5.00/foot. In my opinion it's well worth it.
Like silicone you can get it on and off fitting without ripping it to shreds like tygon and it doesn't harden. It's really nice stuff to work with. If anyone is interested I'll find it and post the link. It is opaque though, so in that regard it's different than the stuff we normally use for glow. You can't see the fuel moving through it. Otherwise it feels and behaves the same.