What areas of contact do you use in order to avoid damaging anything in the delicate frame of the car and its components? Do you place any wood as buffer between the lifting devices and the car? Is it wise to use two blocks of hard wood (I already have two sets of 4"-high, secure wooden ramps that I have been using) under the wheels on the side opposite to the one placed on jack stands (with chocks nailed on the blocks of wood to improve stability and safety) in order to keep the car level so that it will be flat on the lifting devices' contact areas and not resting on them precariously at an angle?

Please contribute any useful ideas that come to mind relevant to this topic, and please make it as clear as possible, even at the risk of being redundant (I am using these tools for the first time and, given the potential danger involved in working under a car supported this way, learning how to do it safely is of foremost importance to me...)

TIA,
Rino

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1979 240D, W123, 105K miles, stick, white w/ tan interior.