FiTech EFI system

Talked to FiTech today and after numerous changes to the settings we both agreed that I need to change the return line. I used the existing 3/8" factory style line that has at least 10 different bends from the engine bay to the fuel tank. Thinking that this is disrupting the fuel pressure with the high resistance of the return.

Have any of you guys used their online kit and had similar sympotma? It's over $100 for 25' of fuel line so I'm looking at all options before I drop more $$$.

On a side note does anyone know what the return pressure is coming from the FiTech TB?