I'm upgrading fuel system on '83 S130. Under the hood - Stainless Braided/PTFE lines, Fuel Regulator, Fuel rail, etc. In the rear - Fuel pump, filter, lines. The rear lines are where I have a question. I want to replace everything between tank and hardline with PTFE, just in case I ever want to run E85. Are there any options other than cutting the flared end off hardlines and sending unit connections and using hardline-to-PTFE fittings? Would the large vent hose from tank to filler tube also need to be PTFE? If there is already another thread on this please link me to it - I couldn't find anything. Thanks.