I found this cool tip out by accident, its about filling in seems and gaps, instead using filler or Milliput or stuff like that.  For assembling my kits I use Testors clear part cement.  Then for filling I find that if  one squirts some clear white glue (any brand) into in the seam, then quickly wipe it away with a paper towel dampened with warm water wiping evenly across the surface of the plastic.  Let it dry, then paint it, it looks perfect, I would include photos but I have no camera.  This technique works especially well when connecting clear parts to a model

Josh Henderson