2001 911 Carrera C2/996 Jacking 996 on to Jack Stands

Vehicle Information: Model: 911 Carrara C2/996; Year: 2001; Body Type: Coupe; Total Mileage: 51000;

I have read all the submissions on jacking here, and seen some excellent ones on the renlist forums as well, however I would like to be sure that the lifing proceedure I am using is okay. First I lift the car from the rear jack pad with a floor jack high enough to get a 3 ton Sears jack stand under it and repeat this on the other side. I now have the front end in the air on the front jack pads. Then I carefully jack the rear center casting on the engine, just ahead of the sump. After I get it to the proper hight I install the rear jack stands on the rear pads.My problem is that the car is not really high enough to work under without scraping my nose on the car. I plan to purchase taller 6 ton (20+ inches high) and try to get the car high enough to work under without being claustrophobic.My main question is this procedure acceptable, or should I jack from the rear suspension casting which mounts to the frame? They look plenty beefy. I use a 2" thick Oak block on my floor jack to precisely position the jack on the rear casting, or anywhere else for that matter.