I've done it by cannibalizing parts from a 10w pad and securing them to the underside of a panel in front of my cup holders on my 2nd gen. There are a lot of variables with pads and how much material they will tolerate and what types so you may need to experiment. Coil alignment is key to getting good performance out of them. I lucked out and the Note 9 and Note 20 both have basically the same dimensions and they fill the space perfectly once I upgraded so I can just toss my phone in and it works perfectly everytime. Its powered by splicing in a 12v pigtail to the switched 12v that is located just above it as I don't use it for anything else and I feel better knowing its off w the key.
Just keep in mind if you change phone sizes drastically or don't have a way to keep a phone in a particular spot they may not work as well as you'd hoped. Thats just wireless charging in general unfortunately.
The pad I used for the components was the Insignia 10w. Very easy disassembly and had a large coil that was able to tolerate the thickness of the trim panel as well as my otterbox defender. There is now a 15w version available but I haven't torn one down to see if they are similar in design and performance. The samsung 9w and up (I know someone who used one in a similar fashion, but in a piece of furniture rather than a vehicle) chargers would be great candidate albeit a bit pricey in comparison but they have active cooling if it is something that concerns you. I have fast charge disabled on my phone so it defaults to 5w anyhow, I use it to just maintain charge level w a trickle essentially while using android auto on my commute. It barely gets warm to the touch where most fast wireless will be noticeably hot after a long charge session or using the 15w rapid charge option.