I want to Plasti Dip the wood grain and and chrome parts in my interior. Also, how would I dip the door handles?
Rather than taking things out, personally I would just tape off the area around each vent using blue painters tape and spray it that way. I know it's kind of a risky preposition to spray inside the vehicle, but plasti-dip will always come off if it gets on something it is not supposed to be on.
I have had multiple times where I got lazy and just sprayed my mirror caps without taping off the exterior paint. The excess plasti-dip has rubbed off the paint every time without harm. However if those vents went on, they can come off. I just imagine those things break easily. Maybe try youtube for someone removing the dash assembly, I bet those come off as part of the process.
Just be sure to tape up anything sensitive such as digital screens, instrument clusters, etc. No idea what comes in the 3rd gens so I am just throwing it out there.