With my side skirts and front added I can't get a jack under either, I've brought a jack that's meant for lowered cars it works for the back but not sides or front still!! (Doh)
I went back to use the normal jack supplied with the car and it works best on the sides, prop up one side stick the car on a stand, back down with the jack then the same the other side!! A bit of a long winded way but works for me!! :D