JARblue

A couple of screw holes (use a nice step bit), a good bit of tape, and some patience lining everything up is really all you need. It may not fit absolutely perfect, but the screws and tape should help everything come together nicely. Really, there's nothing mechanical about it.

If you can't get your car up on ramps or some jack stands, don't bother trying to DIY it. And you should never work under the car if the only thing holding up your vehicle is a jack. The OEM scissor jack and other floor jacks are not designed to hold the vehicle while you work on it - that's what jack stands are for. Like Mr. Kenchan mentions, the OEM jack can fail or tip over way too easily. Floor jacks aren't really prone to tipping, but they certainly aren't designed to hold the load for long periods of time (like while you work on the car). Eventually it will fail - please make sure you are not under the car if this happens.

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