THIS IS HOW YOU INSTALL THE 3 TRIM PIECES:
Yes, I've done it. Just yesterday. Use the new pieces to find the location of the tabs as a guide on locations to pry with your plastic pry tools. Yes, you need it. They're less than $10. $5 at Harbor Freight and I think $3 or less from Aliexpress.
The biggest tip is for the middle piece under the infotaintment screen as others have said. It's true that it's easier to remove the stock piece b/c it's plastic and has some give whereas the wood one is thicker and much stiffer giving it a lot less tolerance. Once you pry the piece loose, the hard part is to remove it since the screen is in the way. I was frustrated with it for maybe 10 minutes but figured it out by total accident.
The secret is that once it's completely loosened, you'll find that it's one tab that's stuck - the one closest to the infotainment screen and back of the glove compartment particularly if you have the wide screen version of the i3. Do this with the glove compartment open. It'll give you more space. Rotate the entire middle piece counter clockwise about 90 degrees or a bit less so that it's only the far right (for left hand driver cars) tab is stuck in the slot. That's the bugger that's hard to get out. You'll just need to stick your finger in there and help it with some firm pressure. Very firm. Did I say firm. Yes firm. Use your finger so you can get a good feel of it and you're not going to accidentally put too much pressure, let a tool get loose and scratch something.
It's really about the piece being rotated in the correct position before even attempting to remove the last tab up and out. If you don't rotate the piece almost 90 degrees counter clockwise, I don't think it would ever come out. Orientation of the piece is key. It should face the long direction. Driver-side end of the piece pointing at 7 o'clock and the passenger end of the piece that's "stuck" needs to point at 2 o'clock.
If you're having trouble still, keep experimenting with the angle of the middle piece. You're essentially rotating it about 85 degrees, not quite 90. Have at it. Don't give up. You're almost there. It's not going to come loose on it's own. Remember you need to pull it up and towards you firmly with a finger once you have the piece at the correct angle. All flat in the up/down direction. You're just rotating it to the right hinging on the trouble tab.
PASSENGER SIDE PIECE:
Open the glove compartment to expose the two torx screws underneath. Remove those two screws, then use a pry tool and pry the gently and then lift with the pry tool. The tabs are stronger than you think.
DRIVER SIDE PIECE:
Use a pry tool to lift and pull the AC vent piece loose so that you have better access to the perimeter of the small dash piece there that you're replacing.
Do the glove compartment passenger side first. It'll give you the confidence to do the center piece. Then do the center piece so you can feel proud of yourself like you made such an accomplishment. Chances you're doing this alone so you'll have to pat yourself on the back while your wife is sound asleep as are your kids. Save the driver side baby piece for last since it's easy but has the extra challenge of loosening the AC vent first.
A fanatic of all things electric. Ridables like electric ice chests and stand up scooters I adore. Drones like DJI, I root for. I'm a fan of both, but nothing beats my love for my 2016 i3 Rex with Deka World. Shhh, don't tell my wife.