For what its worth, I built a fuel polishing system based on the one that Patrick Laine demonstrated in his You Tube videos, and purchased connections from our local supplier of hydraulic fittings and connections that I was able to insert into the fuel lines just outside of the fuel tank. This was on my B36(2002), where the fuel suction and return lines came out of the top of the fuel tank where there were metal elbows and a straight couplings already in place. I purchased two “T” pieces and two stop ends so that the fuel polishing system could be coupled in easily when I wanted to use it, and after I’d finished the polishing system could be uncoupled and the stop ends fitted back into the then unused oart of each “T” connection. That meant that periodic polishing could be done whenever I wanted to do it, and I didn’t need to leave open the fuel filler cap and worry if rain might enter while the filler cap was open.
As for those connections, I took parts of the existing fittings that could be undone and removed to my supplier, in order that they could identify the size and thread so that the couplings they provided would fit correctly.
