There might be another possible alternative, if you want to drive a pre-planned route and don't really care about exact street level info or on-the-fly rerouting.

There is this website mapsonus.switchboard.com, if you go to the general options and select 'show latitude and longtitude', it adds an additional link at the bottom of a planned route page "Raw Route Description". That basically contains a well documented dump of the route information, both the turns with descriptions and the actual shape of the path that is drawn on the map.

All coordinates are in NAD27 and I've successfully converted them to tracks and routes for my garmin etrex venture gps, and they seemed to match the actual roads reasonably well.