Check this out
https://www.pistonheads.com/gassing/topic.asp?t=1235452
I have had my 996GT3 up on 4 jack stands many, many times and always use the same procedure which has never resulted in any damage or anxious moments. Here is what I do,
Lifting kit needed;
Low entry jack
Ice hockey puck
4 off decent axle stands
2 off wooden blocks approx 10" high around 12" x 12" (I made these from 3" x 2" offcuts)
Make sure handbrake is on in gear etc and chock the opposite side to which you are working.
Place a jack under one of the rear body jacking points and raise high enough to get an axle stand under the front body jacking point. Place one of the wooden blocks under the rear wheel. Carefully lower the car onto the front jack and the rear tyre onto the wooden block.
Repeat on the other side of the car, leaving your car on two axle stands at the front and the two wooden blocks at the rear.
Then using the hockey puck, jack under the rear transverse crossmember in the centre until you can get the two remaining axle stands under the rear body jacking points, remove the wooden blocks and lower onto the axle stands.
It really is easy and takes me literally five minutes.
Lowering is the reverse, raise the rear a little to get the wheels back on to the wooden blocks and remove the axle stands.
Then use the rear jacking point with the jack to raise one side high enough to remove the wooden block and front axle stand, followed by the same the other side.
Here is mine up having the brake fluid changed early last year.
