Chosen Solution
I have a TI-83 graph calculator (not TI-83 plus), I think, by (c), it’s from year 1996. On the back cover I only see two screw (not 6 as I see here in another teardown). I have remove that 2 screw but can not remove the cover. How can I release the back cover, without broken it ? Thanks.
At the bottom, by the data port, you can get a small screwdriver or plastic tool in the seam on both sides. Then just cautiously work your way around and toward the top; there are some snaps which will come loose. I had the same issue with mine and got so frustrated that I just didn’t care anymore if I broke it! It turns out that was the way to go.