I've recently had the 'down' side on my RX330's driver side temp control give up the ghost. I know this is a somewhat known and documented issue with the car - from what I've seen, this looks like the best option for getting the parts to repair the switch. Before I pull the trigger on getting it printed, I wanted to check if there are any alternatives I might have missed.

As for the installation, for someone who's a complete novice at working on cars, is it likely a DIYable thing? Pulling out the head unit/switch looks a bit daunting based on the guides I've seen, but I'd much prefer to save the (likely) hundreds on labor if I can DIY it. I've heard a couple of people pried off the button rather than remove the entire unit, but I'm a little concerned about breaking something that's even more expensive to fix.

 

Could you post pic? Let me know what happen.
(My english is poor)

 

The link you posted is for a CAD file to 3D print the part and not the actual part itself. Someone posted here they made theirs from a rubber eraser they whittled down to the “right” size. Maybe you can find the size from the CAD file but I made mine using trial & error and a plastic rod of a proper diameter since It’s not rocket surgery.

The real trick is getting the switch cover off and removing the console cover is NOT going to help you much. If you are very careful, you can pop the cover off using a thin screw driver inserted at the pivot point of the rocker switch. I made tool from a very long construction staple that I bent into an L shape with a loop at the other end that gave me a lever I used to pry the catch off at the pivot point just enough to get it to release. I figured this out after the Lexus tech broke one of my covers trying to fix it after I thought they had broken the switch when they replaced my dash. Turns out it is was already broken but my wife never told me that before I took it to the dealer. Anywho, the other side broke soon after and I repaired it myself without breaking the switch cover.

Ps, I found this YouTube video that shows you how to fix it by removing the console cover:

https://youtu.be/gFnb6NFf8Pc?si=b0ZTiAqg2mgP30aT

This is the safest way to do it but also the hardest. At least it will give you an idea of what’s behind the switch cover and you can decide which way you want to go. BTW the Lexus tech “fixed” the cover they broke by wedging a price of folded up paper on the side of rocker switch pivot point they broke prying the cover out to keep the rocker switch from falling out! But, like I said, if you’re careful you can remove the switch cover without removing the console.