I am having trouble with the dual Strombergs on my Series V (who doesn’t). A couple of weeks ago they were leaking around the jet adjustment screws. This turned out to be o-rings made of the wrong material that dissolved in gasoline. Now they are leaking through the vent drilling behind the air filter mounting flange. I didn’t even know the vent was there until this started! Since it’s happening on both carbs, I suspect that the fuel pressure is too high, but I am using only the mechanical fuel pump. (I removed an electric booster pump a year ago.) I noticed that the floats in both carbs were pitched high so I adjusted them to the specified 20 mm above the flange to bear better on the fuel valves. No difference. There’s no evidence of damage to the floats, but do they saturate and sink? I ordered a 1-5 psi pressure regulator from Summit Racing, but this requires a return to the fuel tank. Has anyone put a return to the gas tank in?