[Fire HD 8 and HD 10 Original Android Development] TonytheEE:
5.3.7.0 rooted with open case method. Here are some tips.

Thanks for everyone's input. I bit the bullet and opened the tablet. I have some notes, as I was flipping through the posts, trying to resolve all the different procedures and getting really confused. I decided to put some tips together from my experience:

1) The contact to short is actually under the blue dot. This is fairly obvious when you actually open it, but if you're unclear from the pic and hesitant to open because you're not clear on what's the contact, the blue dot is in the position of the CLK bit.

2) If you haven't bricked it, you will not be "bricking" this tablet, just kind of hijacking the startup method and inserting a custom recovery before everything gets started.

3) Get latest Amonet and Brick-suez.zip. you don't need Unbrick from the retyre guide unless you actually done messed up.

4) You need a T5 Torx Screwdriver. It's not even possible to do this without one, so don't crack it open until you have one. Most little screwdriver kits will have one for under $10 USD. (https://www.amazon.com/Precision-Screwdriver-Pentalobe-AKTOO-Eyeglasses/dp/B07KQFW7QF/)

5) There are three items to unplug: the battery cable (it has 6 pins with red, white, and black IIRC). Lift it from the board. It attaches vertically. Then there are 2 ribbons. Get some needlenose pliers for this. There is a hard plastic tab that covers the delicate orange ribbon. Pull on the tab, one corner at a time, gently. after you get a little budge on one side, go to the other, and repeat until the ribbon comes loose. There's a wide one for the display, and a small one for the front-facing camera. I advise practicing on the small camera one. There's some tape on all these contacts. I just stuck them near their respective connectors to put them back easily when I finished. The camera in the corner has a bit of rubber keeping it in. Pull it off (it comes up easy) and leave that camera with the board. I advise keeping the meat of your hand on the table so that you don't yank it far if it comes out quicker than expected.

6) There is a little tab near the battery cable (6-pin) that holds the board down, you'll need a little screwdriver to pry it up. It's pretty resilient here, so you can get a little force going (do this after you unscrew all 11 screws and remove all the ribbons). There's also some black plastic pins that help locate board (hold it in a particular place). make sure it's popped off those as well as possible before you start prying.

7) Place some scotch tape over the terminals where the speakers are soldered. This will reinforce the connection. Just make sure you have a large enough surface to where you can flip over the board with the rest of the tablet next to it and you'll be fine. Note the little piece of foam on the closest speaker. Try to make sure that gets back in its little slot.

8) Run Steps 3-8 of the retyre guide, but do this in the amonet folder that has ./bootrom-step.sh and use ./bootrom-step.sh instead of retyre's instruction.

9) To be clear, you'll start this script, then do the short prescribed, then plug in USB while holding the short, then the computer will tell you when you can let go of the shorting wire. Get the micro USB end in first, with the Computer end loose.

10) When cutting the jumper, cut one end at an angle so the tip is sharp, so you can better touch the pin. As for the ground end, the bottom side (from post #2's pic) of the SD case has a little hole that works well. Try to make sure the wire isn't hitting any of the pins INSIDE the SD card case.

11) If you can, get a friend to plug in the USB cable while you're holding the short. Note that the script should be running already, and waiting for a bootrom.

12) If it fails, just unplug from the PC and start again by starting the script over (just hit "up" at the console to recall the last command).

13) You're successful if you see "Remove the short and press Enter". Do as it says. Remove the wire and breathe a sigh of relief. Do not disconnect the USB cable at the "rpmb downgrade ok" point. Wait until the script is totally done. You'll be back at the console, able to make commands.

14) As you put the board back in, first make sure you're able to move the 3 cables freely (that you didn't screw the board in on top of them, and put the corner camera back in position. Put the 11 screws in, but don't wrench down. just give it enough to feel resistance then STOP.

15) The black tab I mentioned in tip #6. it might still be under the board and not snapped over. You'll see the board start to warp if you screw it down too much if this hasn't snapped on. Put some pressure on the board in this area (there isn't a lot of stuff to damage in this square cm, so give it a little muscle) until it snaps. Congrats. This is the last hard part. Put the cables back in. The display one takes some extra finesse, but just rock it back in until the little square stickouts on the side of the hard plastic bump up against the connector, or that white line on top is no longer exposed. Battery should come last. Take care with those speaker wires and snap the back case on again.

16) From this point, power up. If it comes on, you're good (YAY!), if not, open it and check your work (sorry!). run the ./Fastboot-step.sh and it'll do it's thing. You have TWRP!

Grab the .zip you want, and if you want Magisk and Gapps, these links should get you started:

https://xdaforums.com/apps/magisk/official-magisk-v7-universal-systemless-t3473445

https://sourceforge.net/projects/opengapps/

I've been enjoying the Lineage 14.1 from ggow, and yeah, camera's still not working. If that is important the 12.1 from him has a working camera. Split screen of Nougat took precedence for me.

Hope this helps anyone who's been squeamish about cracking the tablet open. Vaya Con Dios

Tony

---------- Post added at 03:16 PM ---------- Previous post was at 03:12 PM ----------

I think the small one next to the USB goes to the front camera. There's a wider cable with the number 51 on it by the battery cable. I think that's the Display. Shouldn't it also have the touch?