Main board with the cameras, processor and the rest can be taken apart as well. The thermal camera can be taken out from its connector after removing a thin metal cover. SIM car slots, front, back camera as well.
Mine problem was some corrosion on one chip that can be seen on the pictures if you look closely. I managed to clean it with distilled water, contact cleaner and alcohol. I heated it with a hot air soldering station as well to resolder the chip and assembled the phone. After connecting it to a charger the screen started to work again and the phone is back to full functionality.
I am not sure how water tight it will be after taking it apart and putting it back together again. It seams that we still have to wait for a true water resistant phone.
There is a lot of room inside the phone to put in a wireless charger and solder it to a micro usb connector. Since i will be selling mine i will not do this. But it would be a good idea for CAT to put a wireless charger and remove the micro usb connector. Since the ear phone jack is hard to use with the cover over it it can be removed as well.