I believe I just cut it further back and capped off the vapor line. I haven't noticed any issues. I used the RX8 oem main feed line as a return line and did my own ptfe 6an line for the feed from the pump to the regulator. I also thought about keeping it stock lines but it was really not crazy spendy to do the ptfe lines and a regulator and at the end of the day it is the right way to do it.