We ran the lines along the door sill on the first car we used 3/8" stainless steel tubing anneled, on the car we have noe and the one were building we used .065aluminum tubing, the bulkhead fitting for the carb is located as high as possiable on the passengers side (above the false floor) we used a ss braided line from there to the carb, what we did in the rear was first we cut the compression fitting off the cross over pipe,balance tube, and tig’d a – 6 an fitting in its place we then ran a braided line to the pump thru a filter and then a braided line to the bulkhead fitting behind the pass. seat,we did the same on the brake line except its .028 stainless, we used a filter that can be cleaned, and coupled it directly to the pump which is a 5/6# carter street pump. Im not really worried about the internal lines to answer that question,its just a pain under the car and that did bother me!