I liked how you simplified the explanation for the cooling circuit and reminded me old days. However, in my humble opinion, I would not use fuel hoses since usually they are not tested for high pressure and high temperature levels (vehicle fuel systems are open to the atmosphere and tested with nominal pressure of 0.3bars). I also was not able to see any clamps for the line connections. (Or maybe you added them later on) one last concern would be the package area since hoses are not preformed which might be difficult to make a perfect routing in order not to touch any other components while the engine is running, but, since you are building up the cooling system by your design, using unformed hoses was the only option. Keep up the good work!
Thanks! I'm also weary of the fuel line now that it failed in another non-fuel use setting (trans cooler). I'll go back and replace it with proper heater hose. I have the lines secured to the frame rail, and am heat shielding everything.
It's called a Rivnut tool. You can find the kits on amazon. The one I got is made by Astro pneumatic and it's pretty decent for the price. In general it's worth it's weight in gold!
