Question; do you have a pressure regulator also? I always use a regulator and a pressure gauge, as it's good insurance against carb problems, even if you're running a mechanical pump, and a neccessity for an electric pump!
I run my tunnel ram and twin carbs through the regulator, then use one of the regulator outlets for my gauge, and the other goes to my fuel block. My fuel block is a 3 port, so I run in and two out.
I'm afraid of plastic line, so I'm running metal lines on mine.
If you mount it on the firewall you'll need a flexible section from body to engine, but after that I'd do aluminum or steel line.