Simple jack adapter with slot. There is very little plastic in between the car and the jack. Let's hope this will pay out in case the thing breaks. Can be fitted with self adhesive felt on the top surface to prevent scratches and spread the force better.

Works well when printed from Prusament PC with 100% infill (this seems an overkill, but I wanted to keep the risks low)

Update:
Actually the 100% infill PC version cracked after applying some excessive horziontal force. It split into two parts still sitting on top of the jack. It could have been still used, but it did not seem safe.
Instead a v5 version was printed from Prusament PETG 30% infill that fits the wider jack ring. Thanks to its shape it passes the weight more directly to the jack. The 70% hollow PETG provides extra flexibility to prevent cracks. Als, this version is thinner + the jack is thinner itself without the small ring.