OK , for the OP that asked the question, you need to have a good jack and stands, some small stands can be dangerous to use, so pick and spend well on the correct tools for the job, cutting corners and one landing on you is not good, you need to assess the car on condition to where best the car is to be supported , if the jacking points" behind the sill lip" is good ,then she rests on them, this also depends on the job thats being done, if you are welding new sill sections in etc, then a better place thats safe needs to be found and for the safe height to work at or under, always try to get them onto to 4 corners for best support , resting on the
under body floor pan chassis rails is no the best of places for axle stands for one to be safe to get under neither is uneven or a slope,flat solid ground is a no brainer, some of our axle stands will go to 2.5 ’ as will the jack and all rock solid, safe as houses, but that is the height we need to do the projects/builds/ restorations/revamps etc we do with some jobs, brakes and what nots will be rested on smaller stands, …
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