I was researching this due to a humidity problem in my driver's side fog light assembly. It is apparently the same assembly on both the Model Y and the Model 3. The difference is in the amount of room available to reach the attachment screws and latches. There is more room on the Model Y after partially removing the associated wheel well. I fixed the humidity problem (after discovering the cause was an improperly applied "seal" on the back side - it looks like electrical tape cut to size. I used a hair dryer to get the water/humidity out of the light assembly and re-applied a fresh piece of electrical tape over the vent hole. This has worked well for over a month now.
