Diesel sam

Hi recently bought a 2013 insignia diesel, this came with a compressor and puncture goo, but no spare. This I was not keen on so I bought a space saver wheel. So today I thought I would make sure the wheel would fit. I had also purchased the handbook as this was not in the car. The car in question has 19" wheels. The ground clearance under the sills is 4 1/2" front and 6 1/2" rear. I could not get a scissor jack to fit under the gap at the front and locate with the jacking points, the arms hit the sills before it located the jacking points. Also no trolley jack I have will also go under. This is with a tyre that is not punctured. I had to make a small wooden ramp to drive onto so I could get a trolly jack under. If I encounter a puncture on the road I recon the car would only be 2 1/2" above the ground. What does everybody else do to jack up their car?