It is a 1979 LTD Landau. The thing I was keying in on was that I was not finding any other LTD's of this body style with CLEAR turn signals BELOW the dual headlights. All the ones I saw, and they were in the early 1980's, had amber lenses. This car however has clear lenses with amber bulbs.
Check out this page for comparison. Even though the side mirrors are different that can be due to an option package. The car in the posted picture may have the "aerodynamic mirrors" option. Remember, this was the end of the 1970's and beginning of the 1980's so "aerodynamic" would have been a big selling point.
http://web.telia.com/~u65008048/ltd/fordltd.htm
The grill is also identical on this car. The car posted above though is a higher level car because the one on this website does not have the side turning lights that come on when the turn signal is activated, a fancy option at the time.