It is not difficult per se, but a massive PITA if that makes sense, because you have to lie on your back in the passenger side footwell, feet up on the seatback while getting the bolts out of the cover panel under the glove box. (The two front ones are okay, but the rear ones are rather difficult to reach.)
Once that is done, though, there is not much complexity to the job itself, be it the footwell lighting or forcing the radio module on an OnStar diet, if even I could pull that off back in 2018, you can certainly do it yourself. Reinstallation of the rear bolts was where my patience wore out, to be honest
, but maybe you are a saint
Yes, you want to do all your HMI work (front or surround camera kit, footwell lighting, OnStar removal etc) while that panel is off so you don't have to repeat the experience.