Hi EI Chorizo.
I figured it out myself - I removed the push pin on the bottom (be careful don't damage it because it must be reused. There are only four screws in the kit for the Front Mudguard - two screws for each side to use in the wheel well.) After removing the push pin at the bottom, I located the front Mudguard, then use the push pin just removed to push it back in with the Front Mudguard in place. Then I used two screws in the kit to screw the Front Mudguard in the two holes on the top of the push pin in the wheel well. That how I installed the Front Mudguard onto my 2026 RAV4. I didn't know how to remove two push pins in the wheel well, and I don't want to destroy them. Also, there are just 4 screws supplied in the kit - two for each side - so I thought that could be no removal at all and just install over it. That what and how did for the Front Mudguard
On the rear is easier, there are six screws, six metal clips, and two bolts - So I used 3 screws, 3 metal clips, and one bolt for each side. the kit should come with two washers for two bolts, but it doesn't come that way, no washer at all. Luckily, I found two washers in time for the installing, so I didn't have to go to auto store to buy them. For the Rear Mudguard, there are 3 dimples on the rear wheel well to indicate where you need to clip the metal clip on. I hang the three metal clips on to rear wheel well at that location with the flat side facing to Mudguard. Then I removed one bolt at the bottom, after that I relocated the Rear Mudguard in place, then snugly install the removed bolt back in first to keep Mudguard in place, then I snugly installed the second bolt (you should prepare the washer for this bolt because it doesn't come in the kit) on to the other hole that is aligned with the hole on the Rear Mudguard at the bottom of the RAV4. Everything is just snugged tight at this point. Then I screwed in the three screws at three dimple locations that I already hang the metal clips there. While tightening these three screws, I kept an eye on the Mudguard to make sure there is no gap between the Mudguard and body of the RAV4. After tightening three screws, then tightening two bolts and I completed the installation for Rear Mudguard.
By the way, I have another issue as well - normally, when buying a new car, the owner would get the books those come with the car, and one of the book is used to keep track of service, which you have the dealer stamp on the page in the book for what service performed, so you would have a history of service record. However, I only got 4 books on the 2026 RAV4, and there is none of that book in the package. I called dealer, but they said: that is all for the car. I wonder how we can we keep track of the service, or how can we know that is the way it come for the new car now, or there is missing a book in the package.?
Also, I like to have HUP on the car, but my RAV4 has no HUD, I thought that HUD only equipped with Limited version. My is not, it is XSE.