Was up far too late last night looking at various surge tank setups, woke up today and gathered the parts needed to make a prototype from steel. I find that I usually realize a better way to do things shortly after something is built, so I'll do an aluminium one after I know how, or if, I want things to change. On the top I've got one -4AN to use as an inlet from the Facet pump, there is a second -4AN which I'll use as an outlet from the tank back into the stock fuel tank. The third unit on top is a -6AN for the return line from the engine. I actually put two -8AN outlets on the bottom, at almost 90 to each other, as I wasn't sure which way I'll mount the tank and where I would need the outlet.
On the factory fuel tank, I'm planning on using the original factory outlet strictly for the gas heater. Since I have the drain plug out of the tank it makes sense to clean things up and get rid of the T-Fitting I've been using. I grabbed an M20x1.5 oil pan drain plug, drilled it out and welded on a -4AN fitting. Need the paint to dry before I can test it in the car and ensure it will actually work, but might as well make the bits in hopes that it works out!
-Dave