Kite string, paper towel and a vacuum will do the trick. just seal up the holes you arent using, knot the string around the paper towel and stuff it into the mast. Use the vacuum where you want the string to come out and turn it on! The vacuum will suck the paper towel (or kleenex) through the mast and bring the kite string messenger line with it. replace the kite string with a piece of stringer twine and then use that to pull the halyward through!