NUVI 780 NAV mode

In the NAV mode is there anyway to change the display from estimated time of arrival to speed? I know I can touch the EST and get the trip screen that shows speed but than I can't see the route. I really like to use the GPS as a speedometer. My 2610, 60CSx, and Etrex legend all let me do this while navigating. I have a Samurai with really big tires.

I have only had my NUVI for a couple of days and have down loaded the manual and can't find anything about this. Thought maybe one of you might have an answer.

I think I know what the answer is going to be, but I have hopes.

Win

NUVI 780, 2610, 60CSx and old Etrex Legend