fuel return lines question

I have a big leak in my injector vicintiy, i suspect the fuel return lines as they a soaked in fuel and after i run the engine i can see steam rising from where the diesel runs down the hot engine. any way i have a couple of questions about the fuel return lines.
1) can i use bulk fuel hose to do the job (gas engine fuel hose)
2) is it a high pressure hose(i gont think so because they are pressed on)
3) What is the inside diameter of the hose? SAE/ISO
thanks