Paul, I did this last spring for a radio coaxial, as well as extra wires or spreader lights and an anchor light. Instead of plastic pipe I used joined (soldered) 1 1/2" copper water pipe. About three lengths I think. At the end I hacksawed pointed teeth, with half slightly bent inwards and the other half very slightly outwards (further sharpened with a file).
The object is to gradually digest small amounts into the end of the copper pipe which will have to be blown, or poked out from the other end. A tap and turn technique works fine. I also used some WD40 for lubricant to speed things up. Either way progress is not going to be very fast - just steady.
Using plastic, the joint ridges - even when facing away from the direction of travel - are too large to avoid resistance by the foam you are boring through. I actually used most of the copper afterwards for a house project.
Make sure you pull extra wires and/or a drawstring line to simplify future possibilities. Installed uncut cable ties every two feet can reduce the downward pull gravity has on the wires, which over time can break conductors.