I would put the Power liftgate to my infiniti fx, I found a chinese company that produces them for several cars, including Nissan but not infinite fx.
So I asked and he said so:
We do not have a kit for your car yet, there is no plan either.
However, it is possible to expedite the development if we can collect a MOQ 50 units (sharing tooling fee) by using pre-order plan
Please check with your friend to see if they have the needs to meet the MOQ. Thank you!"
The price for kit is €399, it is not too expensive.
The problem is the MOQ 50pz, there is someone else interested?