Not a difficult install even if there is no power. I used a piece of fish tape to poke through the styrofoam from one of the ceiling lights to the fan. If you aim straight you can push it through just above the fiberboard they use on the ceiling. You can possibly use a coat hanger ( make sure it is straight and not a long run with a coat hanger as they can flex quite a bit and get you off course) or maybe a thin dowel or rod with the end sharpened to help it go through. strip the end of a wire and wrap it around the rod or dowel, slightly stagger the ends so you have a sort of taper to go thru easier. The best way is to have the stripped section on the dowel and the other wire attached behind the dowel. tape it all together on th with electrical tape. Make sure the tape is tight and end the wrap behind the dowel on the wire area so it doesn't catch and come off.
The wire terminations used by Winnebago will most likely be the crimp on type. You can reuse them if you are careful with the pliers. Otherwise get some of the yellow electrical wire nuts to replace the crimpon type.
Watch your polarity or you're fan will be running in the opposite direction than you wanted