The tubing on the heads is SS and there is very little weight riding on them. The alum tubing is inside the Tube-In-Hose (TIH) heated fuel lines and has rubber hose on either end so no stress on these fittings.

Here is the tank-side of the TIH. You can see the short length of rubber hose extending from the aluminum tubing to the Hot Fox heated fuel pick-up:



Custom 90gal tank from Wvo and svo diesel to vegetable oil conversion kit | Veggie Garage



F650 dash with switches and OLED for Vegistroke system as well as fuel pressure and VO tank fuel level gauges:



And its a purty truck too!