I've been hunting around for a nice jack for the Model 3. I don't plan on carrying a spare (yet) but I do have a nice tire repair kit and I have repaired many tires. It's not always so easy to repair a tire on the car. Especially if it's 5F out. I want the ability to rotate the wheel or remove it to ease repair.
I went through several Amazon returns. Most Scissors Jack are absolute Chinese crap unless you buy some OEM one for another vehicle. I had almost settled on an electric hydraulic jack that worked great until I realized that it would be to tall if I had a flat.
I found this on eBay. It's an old OEM Porsche Jack. There are tons of them on eBay, this one was mint.
It appears all the Porsches that used this vintage jack are around 3000 lbs. Model 3 is 4000 lbs.
I think because they are so light, strong and compact there is a market for them. There are probably 50 on ebay.
It is the only aluminum scissor jack I could find.
It is rated for 1000 Kg (2200 lbs).
It weighs nothing (40 oz !!), it is very well made.
It will jack from ~2.5" to ~10.5"
You can probably use it fine on the body, I plan to only jack under the lower control arm (much easier, safer and only needs 2 inches of lift).
There is a nub on top that I plan to remove. If you wanted it for the body you could trim that nub to fit exactly.
Not sure how much lift you need on the body (part of the reason I hate jacking up from the body).
But you could raise the jack on something to bring it flush before jacking. The jack has 8" of throw (not a lot).
When sizing a jack you want it to go from flat tire on ground to fixed tire off ground.
I ordered an extension crank from amazon. It probably weighs more than the jack.
This image is with it lifting the Model 3 front wheel.
I might be able to use this foam insert as is, in the lower trunk to keep it in place. (iPhone 6s reference, not a plus)