If you are installing the front button, think about where you want it placed. Mine is on the left side, just a little under the dash (it’s out of my view unless I lean to look for it). This is in an unobtrusive place, but the down side is that I really have to lean forward to reach the button.
Fortunately, it’d be rare that I would need to use it since the person putting and taking things from the trunk would normally close the trunk from outside, when they’re done.
However if I were to do it over, I’d probably put the button closer to where I can reach it. I saw one person put it on the bottom of the seat area. It looks easy to reach and you won’t see it while driving (the button glows slightly red). The only problem I could see would be accidentally bumping the button might be more risky in that area.
Also, I have mine powered from the spot under the driver’s side dash. I have never had a problem with it there, but I have heard that wiring it from the passenger side may be more reliable.
Finally, when you mount the control box, I’d make sure it’s not too hard to reach. On the rare occasion you need to update the firmware, you’ll need to insert a micro SD card in it, and it’s possible to drop the card if you’re not careful.
All said, I’m very pleased with my power liftgate. It looks like it came with the car and has been quite handy.