Agree with cautions expressed already and can report I've never encountered any problems with the strength of the jack mounting points on a 240. I have crunched frame rails a bit sticking wood blocks under them however.

Was wondering what bricksters thought of a method I've seen used at a u-pull-it yard. They use 8 wheel rims to support a car, 2 rims at each corner. One rim is flat, the other sits vertically on the flat rim and "locks" into the bottom of the car. The cars seem to sit rigidly on this set-up. Of course, they have you sign an injury claims waiver before entering the yard.