Howto display multiple symbol values in collection_select()

i have the following code:

controller:

@vehicles = Vehicle.find(:all, :order => “license”)

view:

<%= collection_select(:mileage, :vehicle_id, @vehicles, :id, :license)
%>

what i want:

instead of just license, i want:

:make + " " + :model + ", " + :license in place of just :license.

obviously, this doesn’t work. nor does putting an instance variable in
place of :license.

any help would be appreciated.