Following Route 66

I have a new GPS, the Garmin Nuvi 650. Unfortunately, the Nuvi line can not
do multiple routes or route planning on a PC. It can only have one
destination at a time and only one "via" point. It is not possible to do
route planning using MapSource on a PC and then transfer those route(s) to
the Nuvi.

The Nuvi can have multiple Favorites (waypoints) but only one can be
selected at a time. There is no way to manually override the route the Nuvi
picks to get to that Favorite. In playing with it, the Nuvi prefers to
route via the modern day replacements for the old 66 roads, which is
understandable.

So I see no way to use the Nuvi for a Route 66 trip. The number of
Favorites it would need to make it from Chicago to LA on the roads of my
choice might number in the hundreds, an unmanageable number. I doubt the
Nuvi could hold enough Favorites to keep it nailed on a 2.5Kmile route of my
choosing.

Can anyone think of a way to use a Nuvi 650 to follow Route 66 westward?

Bruce.