[Longhorn Man]

I've ripped mine off of every truck I've owned

We all know that if you increase pressure, you increase the boiling point. That's why we pressurize the rad, to keep the coolant from boiling at 212 degrees (talking straight water)
Now, if you decrease the pressure, then you are decreasing the boiling point. Any restriction between the pump and the tank will cause a decrease in pressure, just like when your milkshake is too thick and you suck so hard that the straw colapses.
Vapor lock is nothing more than boiling gas in the fuel line and/or in the carb.
Reduce the number of restrictions in the fuel line before the pump, and you reduce the odds of boiling the fuel.

That sock was certinaly a restriction, and did in fact reduce the boiling point, and MIGHT have been the vapor lock issue. Throw it away and put the tank back together. Install a quality filter after the pump (like the one you described above) and call it a day. With your guage you will probably see the improvement