How has it been starting since the fuel filter was repaired? Any better? Maybe some air getting into the fuel system. Also I know that the 7.3's don't start well if a few glow plugs are bad. Have you checked them? My old PS needed to be plugged in under 30 degrees until the glow plugs were replaced, then it would start unassisted down to about 0. White smoke is usually unburned fuel, which kinda leads me to the glowplugs. Does it hit on a couple of cylinders, and you still need to crank until it picks up the rest? Will is start fine if the truck is warm?
Michael
Michael