I have been using the front of the engine cradle on my 1999 SE for some time now for the front end, and setting the jack stands on the cradle by the control arms.
As far as the back,I have large 3 ton jacks, and I always have simply stuck it under the center of the rear where the control arms attach to the body {not 100% sure if that's the correct place, but I used to do that for my 1988 GLS tempo for 15 years I had it, worked fine for the Tempo and my Contour}
I have set the stands on the underbody hoist pad areas.
Just want to make sure on a good level surface. Last think you want is your contour making you into a pancake on the floor...