As
Dragin stated the FPR (Fuel Pressure Regulator) is fed from the fuel manifold block maintaining pressure at the injectors and the return to the aux fuel tank is low pressure

Hose is measured by I.D. and you should use
5/16" Fuel Injection hose because of the pressure. I would also suggest that you use F.I. hose clamps. NAPA carries the hose and clamps. F.I. hose clamps have radiused edges and is a nice touch if available.
Here's a thread to my mod Thanks to JSHRAM & BILLH1943:
http://www.rswarrior.com/forums/topic.asp?TOPIC_ID=32523Also, check my Homepage. There is a folder 'FPR Relocation' that shows the F.I. hose sleeved with a fine spring for added protection!