Using some internet tips I was able to complete this repair successfully, I'll summarize here.
When you turn on the calculator the screen has garbled gibberish on it, this is the fix to get it back to proper operation. You need to replace the ribbon connector with your own soldered wires.
First of all, the only picture I got, the work in progress: (you can see my helping hand clip poking into the frame)
You'll need a few supplies on hand before you attempt the repair:
Torx T6 screwdriver
30 Ga. wire
a "third hand" device helps a lot
Remove the batteries, remove the screw for the small "watch battery."
Use the T6 driver to get the remaining screws out.
The case won't pull apart, there are two clips on the bottom sides, and one on the top edge, inside the case, that you need to press in with a small object to release the two sides of the case.
Once you've got it apart, remove the two screws holding the ground plane plastic shield thing in place, then unstick the sticky part of it and remove the whole thing.
Now you need to remove the ribbon connector. I used small needle nose tweezers to get it loose of the main PCB, and the screen PCB.
Then I applied some 99.9% isopropyl alcohol and scraped off the sticky residue with the small tweezers. I cleaned the are with more alcohol. The PCB copper pads should look shiny now.
I also cut away the bottom part of the ribbon, a black sticker, with nippers and a razor knife.
You need to cut and strip 15 small 30 ga. wires and tin both sides of them. You need to tin all of the copper pads with solder also. You need two pieces of 24 Ga. wire for the power pins, the bigger pads. you might get away with the 30 Ga. here but I used 24 wire.
Now, using your "helping hand" tool, carefully solder all of the wires to the main PCB. See my photo for the orientation of the wires. It should only take a little heat to get them connected since everything has been pre-tinned.
Once you've got all your wires connected, making sure you didn't make contact with any of the components or bare pads near the ribbon connector pads you soldered, you can replace the screen assembly, and one by one, bend over each wire and solder them in place to the screen. This is the "fun" part.
Inspect your work closely, being mindful of cold looking solder joints, or solder bridges, or unintentional shorts.
Now you can put it back together, and if you're tenacious and lucky, it should work. I think it took me about an hour or so from start to finish. One less thing going in the landfill today.
