Ok I have a good one, removed pump assembly, took out the relief valve, still surging (has AEM E85 340LPH pump but only running 98 atm)... It was starting to be ridiculous so I thought unless my pump has been removed before maybe ford got it wrong. Check return line oh no fuel. Check vent line oh wow some fuel. Check ford diagram fuel pump assembly (below) mine is not like that its different unless its changed for some reason. My return runs back under vent line and continues across. Anyway, hooked it up, NO surge way under a quarter, only has relief valve taken out (standard pot). If you are getting surge I would be checking that line. Mine also drove fine hooked up the wrong way until I got low on fuel 1/4 etc because it was retuning through the tiny vent.
https://goo.gl/images/FxY5xW