This method negates any problems with un-even workshop floors, and whilst the car might not end up 'level' as far as a spirit level is concerned, it'll be much healthier than simply plonking it on four axle stands and hoping for the best. Usual internet stuff applies: if you're hard-of-thinking, and end up squashed under your 911 because you've used Lego instead of stands, or have a garage floor made of porridge, don't come running to me
.Anyway, hope this is of interest:
You will need: Two pin, or ratchet style axle stands, two threaded style stands (often used for mobile home support), one mechanical jack (threaded or scissor), plus a heavy duty hydraulic trolley jack.
1) Photograph and measure door gaps with car on level ground. Operate doors to remind yourself of shut-action.
2) Jack the car under the engine (using a suitable protecting pad) and support on pin-style stands under torsion tube end covers (to medium height).
3) Jack front of car at centre of tank support / front pan using a suitable protecting pad. Support under front A-arm mount with two threaded style stands.
4) Return to rear and jack to working height, raise pin style stands to suit.
5) At front of car, now jack to one side to allow centre of tank support / front pan to remain clear. Put standard axle stand here to allow for comfortable working height.
6) Release jack.
7) Place a threaded axle stand under each A-arm front support and raise until stand just touches each (touches but no pressure).
8 ) Raise each of the two outer threaded stands by one full turn, and remove centre axle stand.
9) Return to rear of car, and place a mechanical (not hydraulic) jack under engine (towards rear, you won't be putting much weight through it), and raise little by little until door gaps and shut-actions return to their pre-jacked state.
The car is now suspended in a safe manner, with no additonal distortions over and above it's on-wheels state. Please note, this method does not correct pre-existing errors in shell alignment, but does ensure no addtional errors are built into a car during works. Do not be tempted to use any hydraulic jacks as supports during works, as quite aside from safety issues, they will sink over typical timescales that these works tend to expand into.
The threaded style stands aren't usually as heavy duty as pinned or ratchet ones, but are easily heavy duty enough for the front of the car. A very-much second rate solution is to shim conventional stands at the front to get the front end to match the rear, but you don't get the same 'feel' for the levels then.
HTH
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