Another trick for fishing a pull string through longer runs is to use a vacuum. Tie the end of the line to a plastic grocery bag and shove in one end. Then at the other end use a strong vacuum hose to pull it through. A shop vac works very well. You just have to create a half-decent seal if the hose doesn't fit the conduit end exactly.
I've done this several times when running cable for a convention. In that case the conduit walls were smooth, but it probably will work even with the corrugated stuff if you have enough suction.
If it doesn't work, or for shorter distances I guess a fish tape would be easier.
Looks like you have done a very nice job. I'm sure the finished product will be spectacular.
