Yes it is low pressure. The gm style line kit is available here: http://leroydiesel.com/products/injector-return-hoses-with-clamps/
I have had good luck over the years using the line from Mercedes dealerships, but most the stuff online has high failure rate.
Viton will not harden until +400 deg f & - 20deg f.On the line for chainsaws, lawn mowers, etc- the line they commonly sell gets brittle with heat. I tried a few different brands of that stuff over the years. Heat it one of the issues i want to test with the stuff i just bought
Have you done anything with the line yet. I’m planning on giving it a try when I replace all of my fuel lines when I put in the metrum rod and add the two new filter heads and fuel filtersViton in clear is the hard part. I never found any. The stuff i got from fuelline.com is not viton.